feat: Phase 0 mobile app scaffold — Expo 55, SQLite, Feed/Import/Settings screens

docs/mobile-app.md

@@ -51,6 +51,51 @@ server uses. Any tool in any language can read them.
 
 ---
 
+## Setup
+
+### Prerequisites
+
+| Tool | Minimum version | Notes |
+|---|---|---|
+| Node.js | 18 | 20 LTS recommended — install via [nodejs.org](https://nodejs.org) or `nvm` |
+| npm | ships with Node | |
+| Expo Go app | latest | Install on your phone — scan the QR code to run the app instantly during development |
+| Xcode | 15+ | **macOS only, iOS builds.** Install from the App Store, then `xcode-select --install` |
+| Android Studio | latest | **Android builds / emulator.** Includes the SDK and `adb` |
+
+You do **not** need Xcode or Android Studio to start. Expo Go lets you run the app
+on your physical device by scanning a QR code — no native build required.
+
+### First-time setup
+
+```bash
+# From the repo root:
+bash mobile/setup.sh
+```
+
+The script checks prerequisites, installs npm dependencies, and generates the
+required Expo type declarations. It prints next steps when done.
+
+### Running the app
+
+```bash
+cd mobile
+
+# Development server — scan QR with Expo Go on your phone
+npx expo start
+
+# Run on a connected Android device or emulator
+npx expo run:android
+
+# Run on iOS simulator (macOS only)
+npx expo run:ios
+
+# Build a standalone APK for Karoo sideloading
+npx eas build -p android --profile preview
+```
+
+---
+
 ## Repository layout
 
 The mobile app lives in `mobile/` inside the main bincio repository (Option A).