# apple/ — native iOS/iPadOS app plan

Native **SwiftUI** application for iPhone and iPad, written **from scratch** (not a Capacitor
wrapper, unlike the Android app under `ui/android`). This document is the **source of truth and
continuity** for the effort: it lives in the repo so it travels to whatever machine does the work —
in particular the **Mac Claude session** that does the actual building. Read it first; append to it
as decisions land. Nothing here is final until built and verified; any decision can be reopened.
Items still open carry an **[OPEN / TRACKED]** or **[GATE]** marker.

Chat with the owner is in Russian per the user-level guide; this doc, like all repo docs, is in
**English**.

---

## 0. Working model — two contexts

- **Mac (primary).** All real development happens in a **Claude session on the Mac**: SwiftUI code,
  `xcodebuild`, Simulator, tests, screenshots, signing, TestFlight/App Store. The Apple toolchain is
  native there.
- **Linux dev-host (this repo's usual environment).** Used only to **lay groundwork for CI** (a macOS
  runner, later) and to edit platform-agnostic Swift packages / docs. It **cannot** build or run an
  iOS app — SwiftUI/UIKit and the iOS SDK exist only inside Xcode on macOS. (Swift the language runs
  on Linux, but that is server-side Swift, irrelevant to iOS UI.)

Consequence: the heavy loop (build/sim/screenshot) is Mac-only; keep the SwiftUI shell thin and push
logic into plain Swift packages — good for testability regardless of host.

---

## 1. Tooling to install / verify on the Mac host

Do this first on the Mac before any code. The owner already has Xcode + Command Line Tools + a
simulator installed generally; the steps below are mostly **verify**, a few are **install**.

### Verify (already present, confirm versions)
- **Xcode 26** (latest) — we always build against the **newest SDK** (this is what grants the iOS 26
  Liquid Glass appearance to standard controls; see §3). Confirm `xcodebuild -version`.
- **Command Line Tools** — `xcode-select -p` points at the Xcode 26 toolchain.
- **Swift 6** toolchain (bundled with Xcode 26) — `swift --version`.
- **Simulator runtimes** — need **both**:
  - **iOS 18** runtime (our minimum deployment target — verify the app runs/looks correct there),
  - **iOS 26** runtime (latest — verify Liquid Glass appearance).
  Check under Xcode ▸ Settings ▸ Platforms; install any missing runtime there.

### Install (Homebrew, sudo-free where possible)
- **XcodeGen** — `brew install xcodegen`. Generates the `.xcodeproj` from a declarative `project.yml`
  (see §4). This is the project-management tool of record.
- **swiftlint** and/or **swift-format** — `brew install swiftlint swift-format`. Lint/format gate.
- *(optional, CI ergonomics)* **xcbeautify** — `brew install xcbeautify`, prettifies `xcodebuild`
  logs. Not required for local work.

### No install needed (SPM dependencies, pulled by the build)
- **swift-snapshot-testing** (Point-Free, open-source) — snapshot tests, added as an SPM package.
- **MetricKit** — first-party Apple framework for crash/hang/diagnostic capture; nothing to install.

### Deferred / not now
- **Apple Developer account** — in process; see the gate in §11. Not required to start (Simulator work
  is unblocked without it).
- **fastlane / signing automation** — only when we reach device builds / CI / release. Revisit then.
- **macOS CI runner** (Gitea Actions on a Mac, or a cloud Mac) — the Linux-side groundwork; designed
  later.

---

## 2. Fixed decisions
| Topic | Decision |
|---|---|
| Language / UI | Native **SwiftUI**, from scratch; **not** Capacitor. |
| Targets | **iPhone first**, then **iPad** (iPadOS) as a first-class target: reuse controls, adapt via layout. Possibly macOS/Catalyst far later — do not design for it now, but the `apple/` name leaves the door open. |
| Minimum OS | **iOS 18** (reaches ~A12 devices, iPhone XS/XR and newer; wide parity). Always **build with the latest SDK** (Xcode 26). |
| Directory | **`apple/`** in this monorepo (covers iPhone/iPad/future Mac; `ios/` too narrow, `swiftui/` names a framework not a platform). CI + docs stay co-located with the engine/wire. |
| Project tooling | **XcodeGen** (`project.yml`) + **SPM** modules. Not a hand-managed `.xcodeproj` (merge-hostile `project.pbxproj`, opaque, non-reproducible). Tuist only if modularization outgrows XcodeGen. |
| State management | **`@Observable`** (Observation framework), the idiomatic first-party default. **Not TCA** (heavy boilerplate, steep curve, large dependency; its benefits do not pay off at our size). Introduce a light unidirectional pattern by hand only where genuinely needed. |
| Concurrency | **Swift 6 strict concurrency** from the start (actors / `Sendable`) — cheaper to write new than to retrofit. |
| Localization / a11y | **First-class from the first screen**: RU/EN via String Catalogs, Dynamic Type, Dark Mode, Reduce Motion. Cheap now, expensive to retrofit. |
| Design relationship to web | **Not a mirror of the web app.** Board + game mechanics are preserved; the rest is designed fresh with iOS-native idioms. |
| UI philosophy | **System controls by default, custom only when necessary.** (Also "modern for free": Liquid Glass auto-applies to standard chrome on iOS 26.) |
| Auth | **Sign in with Apple** (required by Apple when any third-party social login is offered) **plus** email / VK / Telegram / … in the usual stacked-button login. Backend already has VK/TG/email; Apple is the only new provider. Details deferred to the descriptive phase. |
| Payments | Target **both** external rails (Robokassa / analogs, primary for RU) **and** Apple IAP, behind a **region-aware payment seam**. See §9 for the out-of-region reject risk (tracked separately). |
| Bundle id | Reuse **`ru.eruditgame.app`** (Apple/Google namespaces are independent; one bundle id for the universal iPhone+iPad app). |
| Design scope vs delivery | **Design/inventory scope = the full (online) app** — describe every moving part up front (online has more by design). **Implementation/delivery may stage** (stub online surfaces + stub engine first, wire real behind the same seams later). These are different axes; do not shrink the *design* to offline-first. |
| Crash reporting | **MetricKit only** (first-party, self-hosted upload; see §8). No PLCrashReporter, no Sentry for now. |
| Analytics | **None.** Nothing is tracked. No speculative "entry points" either (YAGNI; cheap to add later since actions centralize in `@Observable` models). Monitoring stays backend-only, as today. |
| Onboarding | **TipKit** (first-party, iOS 17+) for the coachmark tours, not a custom dimmed-overlay reimplementation of the web coachmarks. |
| Login (v1 surface) | **Sign in with Apple + email + guest.** VK / Telegram sign-in **deferred** to a later delivery (the login screen extends trivially with more stacked buttons). Note: with no third-party *social* provider in v1, SIWA is technically optional (email is not a social login), but we ship it deliberately; once VK/TG land it becomes mandatory. |
| Wallet / store / ad banner | **Designed in v1** (full inventory), **delivery staged.** Keeps the region-aware payment seam + the out-of-region reject risk (§10) in scope from the start. |

---

## 3. Why "min iOS 18" does not freeze the design (reference)

Appearance is governed by the **SDK you build against** + whether you use **standard components**,
**not** by the deployment target. Building with the iOS 26 SDK means standard controls
(NavigationStack, toolbars, TabView, Button, List, sheets, alerts, Form) **automatically** adopt
Liquid Glass on iOS 26, and render the iOS 18 style on iOS 18 — with no per-version code. iOS 26-only
APIs (e.g. `.glassEffect` on custom views) are used behind `if #available(iOS 26, *)` with a fallback.
**Custom-drawn UI** (board, tiles, score) looks identical on every version because we own it — so the
minimum has almost no visual cost for the game's core surface.

---

## 4. Proposed layout under `apple/` (to refine at setup)

```
apple/
  project.yml            # XcodeGen spec (committed; the .xcodeproj is generated, gitignored)
  App/                   # thin app target: @main entry, Info.plist, entitlements, asset catalog, app icon, capabilities, signing
  Packages/              # SPM modules — the real code (merge-friendly, testable; non-UI ones buildable on Linux)
    Domain/              #   game state, rules glue, scoring, turn model (platform-agnostic)
    Engine/              #   Swift port of the move generator/validator/scorer + DAWG reader (parity-pinned) — later
    Wire/                #   Connect-Swift + FlatBuffers client to the gateway (same wire as web/Android)
    DesignSystem/        #   tokens, typography (SF), board/tile visual spec, reusable components
    Features/            #   per-screen feature modules (views + @Observable models)
    DataMocks/           #   mock implementations of the data protocols (the "seam"); powers Previews + e2e stubs
  Tests/                 # or per-package tests: Swift Testing, snapshot, XCUITest
  README.md
```

Workflow discipline (XcodeGen): the generated `.xcodeproj` is a **disposable artifact** — never edit
project structure in the Xcode UI expecting it to persist; change `project.yml` and regenerate. Files
are picked up by globs, not hand-listed. XcodeGen passes through arbitrary raw build settings and
custom build phases, so custom needs are expressible; worst case escape hatches are committing the
`.xcodeproj` or migrating to Tuist — no dead end.

---

## 5. Determining optimization principles
These five shape the architecture from the start (not "add later"):

1. **Push (APNs) instead of a live socket while backgrounded.** For a turn-based game we do **not** hold
   a socket in the background; the opponent's move arrives via **push**. This is an energy-architecture
   decision, not just notifications — it puts APNs on the critical path.
2. **Board rendered with `Canvas`**, not a tree of ~225 `View` nodes (far cheaper in perf and memory).
3. **Engine off the main thread** — move generation, DAWG traversal, scoring, hints run on a background
   actor/Task; the UI stays responsive. Swift 6 concurrency enforces this.
4. **`mmap` the dictionary (DAWG)** — memory-map, do not load the whole thing into RAM; low footprint.
5. **Fast silent boot + spinner-less resume via cache.** Show UI instantly; move heavy init (dictionary
   prep) off the launch path (lazy until first needed). On foreground, render the persisted state
   immediately and **silently** re-establish the stream, reconciling deltas — no blocking overlay. (Same
   spirit as the Android native "silent+fast boot" and the web "offline return-online poll".)

### Lifecycle / background (the mechanism behind #1 and #5)
`ScenePhase`: on `.background`/`.inactive` tear down the live stream, stop timers, release resources; on
`.active` resume from cache + silent reconnect. Respect **Low Data Mode / cellular**
(`NWPathMonitor.isConstrained/isExpensive`). Batch network to avoid keeping the radio awake (radio tail).

---

## 6. Hygiene practices (apply as we go)

- **Memory warnings** — purge caches; watch for retain cycles (`[weak self]` around streams/observation).
- **Kill any animation while backgrounded** (do not tick the turn clock in the background).
- **Low Power Mode** (`ProcessInfo.isLowPowerModeEnabled`) — trim animations/background activity.
- **Reduce Motion** (`accessibilityReduceMotion`) — drop lavish animations (accessibility **and** battery).
- **Thermal state** — reduce load under throttling.
- Let the screen sleep; no needless wake locks. No sensors (geo/motion) — none are needed.

---

## 7. Storage — persist eagerly, do not trust `willTerminate`
There is **no reliable destructive callback** on iOS: `willTerminate` is often **not** called (swipe
force-kill, memory kill happen silently). Relying on catching a "destroy" event is a trap.

Pattern: **persist on the way to background** (`scenePhase → .inactive/.background`); snapshot the state
that matters (in-progress tile placement on the board, an uncommitted move). For the uncommitted
placement, also persist **incrementally** on meaningful changes (a tile placed / removed), **coalesced**
(not on every drag pixel). Data volume is tiny, writes are cheap. Store: SwiftData or plain file/SQLite —
decide at implementation. Net effect: even a silent kill loses nothing; the last valid state is on disk.

---

## 8. Testing — take all three layers

The mock **seam** (protocol-backed data access with `DataMocks`) is both the Preview data source **and**
the e2e stub mechanism.

1. **Unit — Swift Testing** (`import Testing`, `@Test`, `#expect`): domain/logic, engine **parity golden
   tests**, wire **codec** tests, view-models. Pure (non-UI) SPM packages are **Linux/CI-buildable** — a
   slice of tests can run in the ordinary CI without a Mac.
2. **Snapshot — swift-snapshot-testing**: visual regression of SwiftUI views against reference images
   (fixed simulator device for determinism). Valuable for a from-scratch design.
3. **e2e — XCUITest against the mock seam**: the native analogue of the web Playwright mock e2e. The app
   launches with a launch argument that switches to `DataMocks`; the whole UI is driven deterministically
   with no server. Runs on the Mac runner in CI.

Lesson carried from web: the mock e2e **bypasses the real network**, so wire/codec bugs are **not** caught
there — they need the **codec unit tests**.

---

## 9. Crash reporting & analytics
- **Crashes: MetricKit.** `MXMetricManager` delivers crash/hang/CPU/disk diagnostics to the app; we
  **upload the payload to our own backend** and view it in the existing **Grafana/logs** contour — fully
  self-hosted, zero third-party, no paid service. Apple's Xcode Organizer / App Store Connect also provides
  aggregated crashes for TestFlight/release builds for free.
  - **Operational requirement:** crashes are unreadable without **symbolication** → CI **must archive the
    `dSYM`** for every build/release (artifact), else reports are raw addresses.
- **Analytics: none** (see §2). No tracking, no ATT prompt, no IDFA — cleaner privacy labels as a bonus.

---

## 10. Payments — region-aware seam, out-of-region reject risk (tracked)

- Target **both** external rails (Robokassa/analogs, primary for RU) and Apple IAP, behind a **region-aware
  payment seam** (distribution region is set per-country in App Store Connect).
- **The RU situation is a genuine grey/in-flux area:** Apple has effectively disabled IAP for RU accounts
  while external merchants are not yet blocked — hence real apps running both paths. We follow that.
- **[OPEN / TRACKED] Out-of-region payments:** external payment for digital goods is a **rejection risk
  outside the RU region** (App Store guideline 3.1.1). We need a mechanism to route/avoid so we do not get
  rejected. Re-verify current policy at the payments implementation phase. Do not die on this hill; the
  owner's real-world observation stands, but the risk is on record.
- **[OPEN / TRACKED] Cross-platform spend compliance:** must not let web-funded (same-email) chips be
  spent inside the iOS app (see §14 → I). A dedicated payments session will settle the iOS spend-
  visibility. iOS v1 shows the packs but blocks Buy with a soft redirect to the web/Android build.

---

## 11. Gates

- **[GATE] Apple Developer account** (in process). Development in the **Simulator is unblocked without it**.
  It blocks, downstream: running on a **physical device**, enabling **Sign in with Apple** (needs an App ID
  + capability), **push (APNs)**, **TestFlight / App Store release**. Sequence work so these land after the
  account is active.

---

## 12. Audio — future (only if sounds are added)

Two common anti-patterns we must **not** ship, both fixed via `AVAudioSession`:

1. **Never silence the user's other audio.** Category **`.ambient`** (+ `.mixWithOthers`): mixes with the
   user's music/podcast, does **not** interrupt it, and respects the **silent switch**. The typical mistake
   is `.playback`, which stops others — we do not use it.
2. **Never "capture" audio at launch.** Activate the audio session **lazily — only while actually playing a
   sound** — and do not hold it active otherwise; never activate on boot. Avoids the "launched and muted my
   music while playing nothing" annoyance.

---

## 13. Development sequence (the process, agreed)

**Design the full online app up front; build in a vertical slice, then breadth.** Order:

1. **Screen & moving-parts inventory** — enumerate every screen and, per screen, its states, data, and
   reactions to actions (re-imagined for iOS, informed by the web functional domains but not mirroring
   them). *(Next up — to be filled in below as we do step 1.)*
2. **Navigation / state skeleton** — an app-level router; transitions expressed as state (`NavigationStack`
   path, state-bound sheets), not bolted on afterward.
3. **One vertical slice first — the game screen** (with stubs), fully interactive. This is where the
   **design system** (tokens, SF typography, board/tile visual spec) and the **reusable component kit** are
   born — on the highest-value screen, not on a login form.
4. **Then breadth** — the remaining screens along the established patterns; each screen built with its
   controls **and** mock data together (not screens-then-transitions-then-controls in horizontal passes —
   SwiftUI is data-driven, so a screen and its controls co-evolve and transitions fall out of the state
   model).

Throughout: mock is an **architectural seam** (protocol + `DataMocks`), not throwaway — the real
networking later slots in behind the same protocols. The **Swift engine port** is its own workstream
(stub the game during the presentation phase; wire the real parity-pinned engine later).

---

## 14. Inventory — screens & moving parts (step 1)

Seeded from `docs/FUNCTIONAL.md`, re-imagined for iOS-native idioms. Tags: **[keep]** as-is in
spirit, **[re-imagine]** with a native idiom, **[deferred]** designed but delivered later. The
per-screen **moving parts** (states / data / actions) are filled in section by section next, starting
with the game screen (the vertical slice).

### A. Boot / launch
- **Loading splash** [keep] — crossword tiles (ЭРУДИТ / ЗАГРУЗКА / ОЖИДАНИЕ), minimal, aligned with the
  fast-silent-boot principle (no empty flash).
- **Offline first-launch → straight into the lobby as guest** [keep] (as Android).
- **"Couldn't load" + Retry** [re-imagine] native, no web-sign-in fallback.
- **"Client too old" update screen** [keep] native: Update (Store) / Play offline.

### B. Onboarding
- **Coachmark tours** (lobby series + game series) [re-imagine] via **TipKit**.

### C. Auth / identity (v1: SIWA + email + guest)
- **Login screen** [re-imagine] stacked buttons: **Sign in with Apple** (native sheet) + **Email** + **guest**.
  VK / Telegram rows **[deferred]**.
- **Email code entry** [keep].

### D. Lobby
- **"My games" list** [keep] — three sections (your turn / opponent / finished; empty hidden), ordering
  rules, unread dots (red/amber), status-blink, swipe-to-remove finished, server games greyed-out offline.
  Swipe/kebab → native **swipe actions**.
- **Bottom tab bar** [re-imagine] → `TabView`: New Game / Statistics / Settings hub.

### E. New Game
- **New Game screen** [keep] — Quick game (AI / random), With friends (invite / pass-and-play), variant
  pick (gated by preferences), RU "multiple words per turn" toggle, per-kind caps 🔒 prompts.
- **Friend invite** [keep] — pick from friend list.
- **Pass-and-play setup** [keep] — host PIN keypad, player rows (2–4), optional per-seat PIN.

### F. Game — VERTICAL SLICE (step 3)
- **Game board screen** [keep] — board on **`Canvas`**, rack, action bar (combined pass/exchange, hint,
  shuffle, confirm), on-board legality preview + score badge, bag count.
- **Scoreboard header / seats** [keep] — opponent cards with add-friend 🤝 / block ✖️.
- **Move history** [keep].
- **Comms screen** [keep] — 💬 chat / 🔎 dictionary tabs.
- **Dictionary word-check** [keep] — complaint, external reference link (network-gated).
- **Hint** [keep] — lays suggested tiles; vs_ai 🔒 idle-gate + countdown (steady in-app timer).
- **Pass / exchange** [re-imagine] native sheet.
- **Pass-and-play in game** [keep] — seat PIN unlock, leader controls (skip / remove / end early).
- **Connection-lost banner + frozen play area** [keep].
- **End-of-game + export** [keep] — GCG + PNG via the native **share sheet**.

### G. Social / friends
- **Friends screen** (Settings → Friends) [keep] — list, one-time code (issue / redeem), requests,
  block / unblock / unfriend; kebab → native **context menu**.
- **Incoming invitations** [keep] — accept / decline.

### H. Profile & settings
- **Settings hub** [re-imagine] grouped `List`: settings, profile, friends, wallet, about.
- **Settings** [keep] — language, theme, board bonus-label style, reduce-motion, zoom-the-board,
  notifications-in-app-only, block toggles.
- **Profile** [keep] — display name, timezone, away window, variant preferences, sign-in methods
  (link / unlink / merge), delete account; inline editing.
- **Merge confirmation** (irreversible) [keep].
- **Delete account** [keep] — mailed code / typed phrase.

### I. Wallet & store (designed in v1, delivery staged)
- **Wallet** [keep, deferred delivery] — balance (per-platform chips), Active line, Buy / Spend toggle,
  watch-ad option, Exchange confirm, store-compliance warnings. Region/store-aware; ties to the §10
  payment seam.

### J. Feedback
- **Feedback screen** [keep] — message + single attachment, reply display, feedback-banned state.

### K. Info / legal
- **About** [keep] — version, links.
- **Legal docs** (EULA / privacy / offer) [re-imagine] — in-app viewer or Safari, not web pages.

### L. Cross-cutting (not screens)
- **Advertising banner** under the nav (free players) [keep] — component, campaign rotation / colours / urgent.
- **Push (APNs)** + real-time in-app updates — data flows, not a screen (APNs is also the background
  energy model, §5).

### Excluded (web / platform-specific — not in the native iOS app)
- **Admin console `/_gm`** — server-rendered web, not part of any client.
- **Landing page** — web-only.
- **Telegram / VK Mini App** hosting + their diagnostic screens — the iOS app is not a Mini App.
- **PWA install CTA** — web-only.
- **Promo bot**, **Telegram support chat** — Telegram-side (in-app Feedback in §J is kept).

### Native idioms replacing web mechanics
`TabView` (tab bar) · native swipe actions / context menus (swipe-remove, kebab) · sheets (popups/modals)
· `ShareLink` / share sheet (export) · **TipKit** (coachmarks) · grouped `List` (settings/legal) · SIWA
native sheet (auth).

### Assets, tiles & icons- **Tiles are drawn as runtime vectors** (a rounded rect + a font glyph + the point value, on the board
  `Canvas`) — **no image assets, no pre-generation, no local-store cache.** Resolution-independent (crisp
  under zoom-on-drop), theme/variant/locale-adaptive for free. Cache rendered tile images
  (`ImageRenderer`) **only if** profiling later shows a need. The crossword loading splash **reuses the
  same tile component** (zero assets).
- **LaunchScreen** is static, OS-level, a simple brand mark (background + logo/wordmark; system font or a
  single logo image — **no tile assets**). Its duration **equals the real launch time** — it **cannot** be
  extended or held programmatically (and fake delays are discouraged); the "longer" splash is the **in-app
  crossword splash** (its timing is ours, shown until the lobby is ready). Match the LaunchScreen
  background to the in-app splash so the OS→app handoff is seamless (no flash).
- **Icons = SF Symbols** (the system icon set) everywhere — all the emoji in this plan are placeholders
  for meaning; the real UI uses SF Symbols (gear, chart.bar, dice, bubble.left, shuffle, lightbulb,
  person.badge.plus, xmark/hand.raised, square.and.arrow.up, lock, …). **Custom vectors only where no
  system symbol fits:** the three variant emblems and the tiles.

### Per-screen moving parts

#### F. Game screen — detail

**Layout**
- **iPhone: full board always visible + zoom-on-drop** (hybrid, web-parity, setting-gated by the
  existing "Zoom the board" toggle). Board scaled to width; on tile drop it magnifies toward the drop
  point for precision.
- **Bottom-anchored stack**, top→bottom: *(top strip — the ad banner (L) + connection chrome, else
  empty)* → **seats header** → **board** → **rack** → **bottom toolbar**. Everything is packed to the
  bottom; the top strip hosts the L banner / Connecting…/Offline/connection-lost chrome, else empty.
- **Orientation: iPhone portrait-only; iPad portrait + landscape.**

**Four regions**
1. **Scoreboard / header** — seats (name, score, whose-turn), unread dot (red msg / amber nudge),
   connectivity state ("Connecting…" / Offline chip / connection-lost banner), 💬 entry to history/comms.
2. **Board (`Canvas`)** — 15×15 grid, placed tiles, staged tiles with on-board legality preview
   (light green when a word forms, darker on run-through board tiles, pink when none; orange badge =
   score), zoom-on-drop.
3. **Rack** — player tiles, drag/tap to place, shuffle, in-rack reorder.
4. **Action bar** — combined pass/exchange, hint (vs_ai 🔒 idle-gate + countdown), shuffle, confirm
   (only when the move is legal), bag count.

**State axes (repaint the screen)**
- **Whose turn:** mine (preview + submit) vs opponent's (draft placement only, position-only).
- **Phase:** waiting for opponent (auto-match "searching for opponent"; resign/chat/nudge off) →
  active → finished.
- **Connectivity:** online / connecting / offline / connection-lost-in-online-game (frozen).
- **Kind:** vs_ai (honest 🤖: unlimited wallet-free hints idle-gated, no chat/nudge/add-friend, no
  clock — 7-day only, no export) · auto-match 2p (possibly a disguised robot) · friend 2–4 ·
  pass-and-play (seats, PINs, leader).
- **Variant:** Erudite / RU Scrabble / EN Scrabble; RU "multiple words per turn" toggle changes the
  preview (main word only vs all perpendiculars).

**Interactions**
- Place tile (drag or tap; the game infers direction) · **blank ('?') letter picker** · recall a
  staged tile to the rack · legality preview on-device (first-time warm-up; server fallback) · confirm
  (only when legal) · resign · shuffle · **hint** (per-game allowance → wallet; vs_ai unlimited but
  idle-gated 30 min, 🔒 + steady in-app countdown) · zoom-on-drop (setting) · **per-game composition
  persistence** (rack arrangement + uncommitted move restored, cross-device).

**Sub-surfaces (from the header)**
- **Seat cards** (with history open): add-friend 🤝 / block ✖️, confirm on a fading ✅; disabled/
  disappear rules.
- **Move history** (words, coordinates, scores; pass/exchange/resign/timeout notes; closing ± endgame
  settlement).
- **Comms** — chat (1 msg/turn, ≤60 chars, no links) + dictionary word-check (complaint, external
  reference link); **nudge**.
- **Pass-and-play** — seat PIN unlock (keypad replaces the locked seat's rack); leader button →
  skip / remove / end-early (leader password); hints and chat off.
- **End-of-game** — result, final scores (yours first), export 📤 (GCG + PNG, never for honest-AI);
  "could not be continued → draw" organizer note.
- **Connection-lost (online game)** — slim banner, play area freezes (rack + move controls disable;
  resign/add-friend/block/chat hidden; a started move stays as a draft); if already in chat/dictionary
  you stay (chat read-only, dictionary keeps checking on-device).

**UX decisions**
- **Comms sheet:** a **single detented sheet** with a segmented control **[History | Chat |
  Dictionary]**; the board + seats header stay visible above; native swipe-to-dismiss + grabber.
  **Opened by tapping the seats header** (where the unread dot / 💬 live). iPad landscape later adapts
  it to a side column. (Simplifies the web's nested history → comms navigation.) The **export 📤**
  lives inside this sheet (History segment, finished game) — **not** in the header.
- **Bottom toolbar (not a TabBar).** The in-game controls are actions, so they sit in a native bottom
  toolbar (`ToolbarItem(.bottomBar)`, the Safari/Mail pattern), **not** the app `TabView` — which is
  navigation and is **hidden inside the game**. Layout: **`[pass/exchange] — [hint ⇄ confirm] —
  [shuffle]`** (3 slots). The centre control **morphs hint → confirm** only once a legal move is
  staged (doubles as "you can commit" feedback). **Exchange** is inside the `pass/exchange` control
  (select tiles = exchange, none = pass). **Recall** a staged tile by tapping it — no dedicated button.
- **Tile placement:** **both drag and tap-to-place**; recall by tap; the **blank ('?') letter picker**
  is a popover over the variant's alphabet.
- **Seat cards:** composed from primitives (`HStack`/`VStack` + design tokens, optional `GroupBox`),
  no prebuilt control. Base header shows name / score / whose-turn / unread dot only.
- **Opponent social actions:** **tap a seat card → a mini player panel** (popover on iPad, sheet on
  iPhone) showing the relationship status (pending / friends / blocked) with **Add friend** / **Block**
  (`Button(role: .destructive)` + native `confirmationDialog`). Replaces the web's in-place score-card
  swap.
- **Rack:** shuffle button; reorder tiles by in-rack drag; tap selects a tile for tap-place; freed
  slots render empty.
- **Waiting for opponent (auto-match):** the opponent card reads "searching for opponent" with a calm
  activity indicator (not a blocking spinner); resign/chat/nudge hidden; you may arrange tiles if it is
  your turn; a "you can close the app and come back" note.
- **vs_ai hint-lock:** the hint control carries a 🔒 badge while idle-gated; a tap shows a transient
  "unlocks in N min" popover; the lock lifts live at the mark.
- **End-of-game:** a result plate on the board (win/lose/draw, final scores yours-first); export via the
  sheet (above); never for honest-AI.
- **Connection-lost / offline chrome** (per FUNCTIONAL, native styling): offline = blue header + Offline
  chip; brief blip = quiet "Connecting…" in the header; connection-lost in an online game = slim banner
  + frozen play area (rack/controls disabled, resign/social/chat hidden, started move kept as a draft).

*(F inventory + UX skeleton complete. Design-system specifics — colours, typography, tile visuals —
emerge while implementing the vertical slice, step 3.)*

#### D. Lobby — detail

**UX decisions**
- **List style:** native **inset-grouped `List`** (the Settings-app look — floating rounded section
  cards over a grouped background). Sections: **your turn / opponent's turn / finished** (empty hidden).
- **Grouping (option A — unified lobby):** one lobby, all games in the three state sections. **Local
  games** (offline vs_ai + pass-and-play, which never sync) are **badged inline** with an "on-device"
  marker. When offline, **server rows grey out in place** (un-openable; a tap explains why) — not moved
  or hidden.
- **Fold/unfold:** **opponent + finished** sections are collapsible (`DisclosureGroup`); **"your turn"
  is always expanded** (it is the action section). Fold state is remembered per-device.
- **Bottom `TabView` (app navigation):** New Game / Statistics / Settings hub. (Confirmed: the TabBar
  switches screens; in-game controls are a bottom toolbar, not this.)
- **Row anatomy:** opponent name (or "searching for opponent" for an unfilled auto-match) · a **variant
  emblem** (three distinct icons — Erudit / RU Scrabble / EN Scrabble; **not** a national flag, which
  can't separate the two Russian variants) · unread dot (red msg / amber nudge) · an **on-device badge**
  for local games · a **result** for finished games. **No status icon** (the sections already group by
  status). No avatars (name only). Compact, line-separated. *(Exact visual TBD on the slice.)*

**Behaviour (per FUNCTIONAL, kept)**
- **Ordering:** your-turn first (longest-waiting on top); opponent + finished most-recent first; a game
  with any unread floats to the top within your-turn/opponent (finished keeps its order).
- **Live updates:** a listed game that becomes your-turn or finishes while the lobby is open
  **flashes its row briefly** (the status-icon blink is retargeted to a row-level flash, since there is
  no status icon); the game also moving into the *your turn* section is itself a signal. An opponent's-
  turn change is silent, applied in place.
- **Unread dot:** next to the game — **red** when an unread message waits, **amber** when only nudges.
- **Remove finished:** native **swipe action** → ❌ (per-account, permanent, no undo). An AI game you
  left (resign or 7-day lapse) auto-drops from *finished*; a normally-finished AI game stays until
  removed; no other type auto-removes.
- **Cold open:** loading splash (crossword tiles ЭРУДИТ/ЗАГРУЗКА/ОЖИДАНИЕ) until the list is ready — no
  empty flash.
- **Offline chrome:** blue header + Offline chip; Stats tab disabled; invitations hidden; server rows
  greyed.

#### E. New Game — detail

**UX decisions**
- **Structure:** a top **segmented `[Quick game | With friends]`** + a contextual **inset-grouped form**
  below (consistent with the lobby aesthetic).
  - *Quick game:* opponent segmented **`[AI | Random]`** → variant (emblem chips) → RU "multiple words"
    toggle → **Start**.
  - *With friends:* rows **Invite a friend** / **Pass-and-play** → pushed sub-flows.
- **Variant picker:** **emblem chips / segmented** (≤3 variants); **hidden entirely when a single variant
  is enabled** (the common default — Erudite only).

**Behaviour (per FUNCTIONAL, kept)**
- **Quick game:** AI default (instant 🤖, no wait) / Random (auto-match 2p — drops you into the game to
  wait inside; "you can close the app and come back" note).
- **With friends offline → only pass-and-play** (invite needs the network).
- **RU "multiple words per turn":** default **off**; RU games only; English is always standard, no toggle.
- **Per-kind caps** (AI / random / friend): a start at its cap shows **🔒**; a tap opens a prompt — a
  **guest** is invited to sign in / create an account, a **signed-in** player is told to finish a current
  game. **Accepting an incoming invitation is never capped.**
- **Friend invite:** pick **2–4** from the friend list; the inviter sets the game settings; starts once
  **all accept**; any decline cancels; an unanswered invite expires in **7 days**; shareable as a Telegram
  deep link (on VK the link only opens the app, the code is entered by hand).
- **Pass-and-play setup:** host PIN keypad → "are you playing too?" (yes → first seat takes your name) →
  name players 2–4 (add/remove; a removal asks the leader password) → optional per-seat PIN.
- **Per-game settings set** (inviter chooses for friend games; quick games use defaults): variant · RU
  multiple-words · **move timeout** (5 min–24 h, default 24 h) · **hints** (allowed? how many each) ·
  **leaver's-tile disposition** (returned to bag / removed — 3–4-player games only).

**UX decisions (sub-details)**
- **Cap 🔒 prompt:** a 🔒 badge on the **Start** control (looks unavailable); a tap opens a native
  alert — guest: a "Sign in / Create account" action; signed-in: an informational "finish a current
  game first."
- **Pass-and-play setup** (pushed, stepped): (a) 4-digit host PIN on a custom lock-screen-style keypad
  (no built-in iOS control — composed); (b) "are you playing too?"; (c) player rows as an editable
  `List` (EditMode add/remove; a removal is gated by the leader password); (d) per-seat PIN via a small
  lock toggle in the row.
- **Friend-invite** (pushed): multi-select from the friends `List` (checkmarks, 2–4) → a **settings
  step** reusing the per-game settings set → **Send** (+ shareable link). Setting controls: move
  timeout = native picker (5 min–24 h); hints = toggle + stepper; leaver disposition = segmented
  `[to bag | out of play]`.

#### C. Login / identity — detail (v1: SIWA + email + guest)

**UX decisions**
- **No hard login wall — guest by default** (offline-first, as Android native). First launch drops
  straight into the lobby as a guest.
- **Reusable sign-in sheet:** a bottom **detented sheet** (same idiom as the comms sheet) with the
  sign-in buttons in a **vertical stack** — **Sign in with Apple** (`SignInWithAppleButton`) + **Email**
  (future VK/TG rows append here). **Shown once on first launch, dismissible** — dismiss = stays guest.
  **Reused on demand** from the Profile "Sign in" action.
- **Email flow:** address → **6-digit code** entry → signed in / linked; rate-limit feedback (cooldown +
  hourly cap). **Code-only on native** — the magic link is unused (it opens an external browser that
  can't return to the app; mirrors the installed-PWA case in FUNCTIONAL).
- **SIWA:** native system sheet → gateway validates → create / link the account.
- **Merge on collision** (the identity already belongs to another account): guest initiator = seamless;
  durable initiator = irreversible confirmation. Triggered by sign-in; the merge screen itself lives in
  **H** (Accounts, linking & merge).

#### B. Onboarding — detail (TipKit, native)

**UX decisions**
- **TipKit, native flavour** (confirmed): contextual tips anchored to controls, ordered via **`TipGroup`**
  — **no full-screen dimming, no tap-anywhere-advance**; each tip dismisses itself (its ✕ or performing
  the action). Shown once; per-device eligibility.
- **Two tours:** **lobby series** (⚙️ settings, ✏️ statistics, 🎲 new-game tabs) + **game series**
  (scoreboard header, pass/exchange, hint, shuffle, rack). Localized (en/ru).
- **First-launch sequence:** lobby (guest) → sign-in sheet (C) → on dismiss → the TipKit lobby tour
  (so the sheet and the tips don't overlap).

#### G. Friends — detail (Settings → Friends)

**UX decisions**
- **Structure:** a single **inset-grouped `List`** with sections **Requests** (incoming: accept /
  decline; outgoing: cancel) · **Friends** · **Blocked** (unblock). A toolbar **"+"** opens the add
  sheet.
- **Add sheet ("+"):** **Enter a code** (6-digit redeem, valid 12 h) / **Share my code** (generate +
  `ShareLink`).
- **Friend-row actions:** **swipe actions** — **Remove** (destructive) + **Block** — each gated by a
  naming **`confirmationDialog`** ("Remove from friends?" / "Block this player?").
- Chat / nudge are **not** here — they live in the in-game comms sheet (F). Global block toggles
  (incoming chat / friend requests) live in **Profile (H)**.

**Behaviour (per FUNCTIONAL, kept)**
- Two ways to friend: redeem a one-time code, or a request to someone you've played with
  (accept / ignore→30-day lapse / decline→blocks until they hand you a code). Cancel your outgoing;
  unfriend removes it.
- A per-user block is one-directional and silent; **unblock and unfriend live only here**.

#### H. Profile & settings — detail

**UX decisions**
- **Settings hub** = an icon **`List` of drill-down `NavigationLink` rows** (the Podcasts → Library
  pattern), SF-symbol icons, with room left at the bottom for optional general info later. Rows:
  - **Interface** (⚙️) → display-settings screen.
  - **Friends** (person.2) → G.
  - **Wallet** (creditcard) → I. **Hidden for guests.**
  - **Info** (info.circle) → About + version + legal (K).
  - **Feedback** → J. **Hidden for guests.** Unread-reply **badge** on the Settings tab **and** on this
    row.
- **Profile = a top-right nav-bar icon** (`ToolbarItem(.topBarTrailing)`, `person.circle`; filled /
  initial when signed in) on the settings hub: **guest → the sign-in sheet (C); signed-in → the profile
  screen.** (Duplicated onto the lobby only if asked later.)
- **Interface screen** (display prefs): language · theme · board bonus-label style · reduce-motion ·
  zoom-the-board.

**Guest has no editable settings** — the random nick is not changeable, the variant is always
`erudite_ru`, the timezone is auto-detected (never set by hand). So there is **no guest profile
screen**: the profile icon for a guest opens the **sign-in sheet** (confirms C). It also confirms E's
"variant picker hidden when a single variant is enabled" for guests.

**Profile screen (signed-in / durable)** — an inset-grouped `Form`:
- **Name** — inline `TextField` + validation (letters + `·`/`.`/`_` separator, optional trailing `.`
  or ≤5 digits, ≤32 chars, ≤5 specials).
- **Play** — timezone (UTC-offset picker, pre-filled from the device) · away window (10-min grid, ≤12 h,
  wraps midnight; a two-time range) · variant preferences (multi-select emblems, ≥1 kept) ·
  notifications-in-app-only (`Switch`, default on).
- **Privacy** — global block toggles (incoming chat / friend requests).
- **Sign-in methods** — rows link / unlink; **email is "changed", not unlinked**; the **last** method
  can't be unlinked; a provider that belongs to another account offers the irreversible **merge** (guest
  initiator seamless, durable initiator confirmed).
- **Delete account** — destructive footer; confirm via a mailed code (email account) or a typed phrase.
  Legal-retention removal (not erasure), per FUNCTIONAL.

#### I. Wallet & store — detail (durable only; delivery staged)

**UX decisions**
- **Structure:** inset-grouped — a **balance card** (running-context «Фишка» first, then linked
  other-platform chips behind their logos: VK / Telegram / web / **Apple** as a new context) → **Active**
  line (hints remaining + ad-free end date / "forever"; hidden when empty) → segmented **`[Buy | Spend]`**
  → rows. **No purchase history.**
- **Buy (v1):** the chip packs are **shown** (the user sees purchases exist in the game), but tapping
  **Buy** shows a light message — *"Purchases are unavailable on the Apple platform. You might like
  another version of [our app](landing)."* — a soft redirect to the Android/PWA build while payments are
  not wired. Chosen over hiding so the offering stays visible; unlocking real Buy later (IAP / external
  rails) is then just enabling the path.
- **Spend:** values (extra hints, days without ads) at a fixed chip price; **Exchange** action + a
  confirm `confirmationDialog`.

**[OPEN / TRACKED — a dedicated payments session, not resolved here]**
- **Cross-platform spend compliance (Apple landmine):** we must **not** let a user buy chips on the web
  (email login) and then **spend** them inside the iOS app where the same email is signed in — spending
  externally-funded digital currency in-app violates App Store rules. This reshapes the iOS
  **store-compliance spend-visibility** (what of the balance is spendable on iOS, given there is no
  Apple-funded chip yet). The owner will settle it in a dedicated payments session. Ties to §10.

#### J. Feedback — detail (durable only; guests hidden)

**UX decisions**
- inset-grouped `Form`: **`TextEditor`** (≤1024, live counter) → attachment row → **Send**.
- **Attachment:** one file ≤1 MB (images / PDF / text-log / office / RTF / archives). **"Attach"** →
  menu **`PhotosPicker` (Photos)** / **`fileImporter` (Files)**; **no camera**. An unsupported file is
  refused **without naming** the allowed types; the chosen file shows as a removable chip.
- **After send:** the form clears, "Ваше сообщение отправлено"; while the operator has not dealt with it,
  a locked state "Ожидаем рассмотрения вашего последнего обращения" (Send disabled).
- **Reply** below: "Ответ на ваше последнее сообщение"; links open in `SFSafariViewController`; marked
  read on view; gone after a week.
- **Unread-reply badge:** Settings tab + Feedback row (H).
- **Feedback-barred** player: Send disabled.

#### K. Info / legal — detail

**UX decisions**
- **About screen** (Info hub row): app name · **version** (native build + the client-version) · links to
  the three legal docs · copyright; optional "Rate on the App Store".
- **Legal docs** (EULA `/eula/`, privacy `/privacy/`, offer `/offer/` + live price list): open via
  **`SFSafariViewController` to the hosted URLs** — always current, the offer's price list stays live,
  bilingual handled by the page; no render pipeline duplicated in the app. **Offline:** unavailable
  ("недоступно офлайн").

#### A. Boot / launch & update — detail

**UX decisions**
- **LaunchScreen:** static, OS-level, instant (**iOS cannot animate the launch screen**) — brand/logo.
- **In-app loading:** the crossword-tiles splash (ЭРУДИТ/ЗАГРУЗКА/ОЖИДАНИЕ) shows **only while the lobby
  list isn't ready**; fast silent boot → usually straight to the lobby. Offline cold launch → straight to
  the offline lobby.
- **"Couldn't load" + Retry:** a native screen when an online launch can't reach the backend (a quiet
  retry first).
- **Client too old** (only on an online action, never while playing offline): full-screen, non-dismissable
  — **Update** (App Store listing) + **Play offline** (keep on-device games).
- **"Update available" (soft, not required):** a **transient top banner styled like a native
  notification** — "Пора обновить приложение", **tap → App Store**, **auto-dismiss after 5 s**, shown on
  **every launch when online**. (iOS has no first-party toast → a custom notification-style banner;
  deviates by choice from the web's persistent dismissible bar.)

#### L. Advertising banner — detail (cross-cutting component)

**UX decisions**
- **Placement:** a one-line strip **on the main tabs (Lobby / New Game / Statistics) AND in-game (F)** —
  players spend most time in-game. Hidden in settings drill-downs and modal flows. **In-game it occupies
  the top strip** (the empty space above the seats header), coexisting with the connection chrome
  (Connecting… / Offline / connection-lost banner sit with it).
- **Audience:** free players only (not lifetime-paid, no purchased hints, no `no_banner` role); guests
  see it; appears/disappears **in place** on a property change.
- **Language (native, no bot channel):** the **interface language** (RU default) — there is no "bot you
  play through" here.
- **Not hidden under TipKit** (no dimming overlay, unlike the web coachmarks).

**Behaviour (per FUNCTIONAL, kept)**
- Operator campaigns (weight %, optional window); compete in proportion to weight; a **house/default**
  campaign fills the unsold share; an **urgent** campaign shows to everyone and is the only thing shown.
- Fair weighted rotation; a multi-message campaign cycles in turn; transitions (fade-out → gap →
  fade-in); long-message scroll; timings from the server (`/_gm/banners`).
- Per-non-default-campaign colours (theme-aware set + optional dark override; derived border); urgent flag.