Phone-native security toolkit · Android 8.0+

Fin

Know what your phone can sense. Use its real hardware — NFC, Bluetooth LE, Wi-Fi, camera, and sensors — to understand what your devices broadcast, and how to harden them.

No internet permission. Local-only. Identifiers redacted by default. No ads, no accounts, no tracking.

13.56 MHz NFC, BLE, and Wi-Fi — the radios a phone actually has. Not a break-in tool. Everything stays on-device.

The idea

Your phone is a sensor. Fin shows you what it picks up.

Fin is a polished, phone-native "Flipper-lite." It reads and writes NFC tags, runs a safe Host Card Emulation demo, scans for nearby Bluetooth LE advertisements, inspects your Wi-Fi, and reads motion and magnetic-field sensors.

It's honest about the boundary: a phone can't clone secure credentials, or use 125 kHz proximity and sub-GHz radios. Fin tells you the truth instead of pretending.

NFC Lab Read & write NDEF tags, inspect tag technologies, UIDs redacted by default.
HCE Demo Card A toy challenge-response card on a private AID — purely educational.
BLE Nearby Short, user-triggered scans. No connecting, pairing, or background scanning.
Wi-Fi & sensors Connection diagnostics, magnetometer graph, and a hidden-device sweep.

Also inside

Door-lock self-audit, QR lab, reports, and a Learn library.

Install

Direct APK for your Android phone.

This is a sideload build (package tv.mayoflux.fin). Android may ask you to allow installs from your browser or file manager first.

  1. Download the APK on your Android phone.
  2. Open the downloaded file.
  3. Allow installs from that source if Android prompts you.
  4. Open Fin, accept the safety agreement, and grant permissions per tool as you go.

Reality check

Use it to learn and to harden — never to intrude.

Only test devices, tags, networks, and locks you own or are authorized to test. Fin cannot clone or emulate real access, transit, hotel, or payment credentials; the HCE feature is a labelled toy on a private AID. The hidden-device tools are awareness aids, not guaranteed detectors — weak signals are not proof of hidden electronics.

Version 0.1.1

Download Fin

Native Android security-awareness toolkit. Local-only, redaction by default.

Download APK

Documentation  ·  Privacy  ·  Safety

SHA-256: 3c681a80803624fac5180ee3c953c627c65077e7b04b76036bffe996aa4c7086