SatoshiWatch

Fully anonymous watch-only Bitcoin address monitor for Android. It passively watches your cold-storage addresses (Coldcard, Trezor, …) and alerts you the moment funds move in — or out. No private keys, no accounts, no telemetry.

Features Instant alerts for incoming and OUTGOING transactions (critical alarm — if your vault ever moves, you know within seconds, first in mempool, then on confirmation with block height) Hybrid monitoring: battery-friendly periodic checks (WorkManager, 15/30/60 min) + optional realtime WebSocket foreground service Home-screen widget (4×2): up to 3 addresses with balance, last movement direction and time, manual refresh button On-device address validation with full checksums: Legacy (P2PKH), Nested SegWit (P2SH), Native SegWit (bc1q), Taproot (bc1p) — BIP-173/350 test vectors covered by unit tests QR scanning via CameraX + ZXing (pure offline decoder) Three languages: English, Czech, German — switchable in Settings In-app updates from this repo: manual check, download through the app's own HTTP client (honors Tor proxy), SHA-256 verification before install