スマートフォン上のあらゆる Android アプリは、今や Claude Code にとって開かれた本だ。スタック：Cla

any Android app on your phone is now an open book for Claude Code the stack: Claude Code → REA (MCP) → headless JADX apk → map → trace → spec → build step 1 → npx rea-agents setup step 2 → full JDK 17+ and the pinned JADX 0.7.1 jar. this is where most setups die step 3 → map the manifest, entry points and DEX before reading any method step 4 → investigate_feature walks UI → handler → the one method that does the work step 5 → SPEC.md from behavior only, build your version in a fresh session the big mistake: reading class names. R8 turns them into a.b.c. anchor on strings, resource ids, framework calls the limit: logic hidden in native .so files or packers won't come back as clean Java. and it's static only, no running or patching save this before you pick your first APK