PilferShush Jammer

Block unwanted use of onboard microphone

Features a passive jammer technique that engages the microphone thereby blocking other apps from using it. But does NOT listen to or record any of the audio from the microphone. It uses 0% CPU and no noticeable battery use. However is not intended to be left on permanently due to the variety of triggers that can cause audio_focus_state changes (VOIP etc).

Also features an active jammer that emits tones constrained to the NUHF range of 18 kHz to 24 kHz range. User determined carrier frequency and drift limits with rate for random tone emissions depending on the device capabilities. For instance 20000 Hz carrier, drift limit 1000 Hz and rate slow - will output random frequency between 19 kHz and 21 kHz approximately every second.

Audible artifacts are present during the NUHF tones but this may be changed in a future release. Experimental white noise output may not be very effective at blocking and is a somewhat annoying sound. The device speaker output may not have enough amplitude to block unwanted NUHF signals - testing will determine.


  • Manual start

  • Notification post when running

  • Auto stop and restart when telephony interrupts

  • Currently relies on audio_focus_state changes for auto-switching

  • Active jammer

Packages

Although APK downloads are available below to give you the choice, you should be aware that by installing that way you will not receive update notifications and it's a less secure way to download. We recommend that you install the F-Droid client and use that.

Download F-Droid
  • Version 3.0.1 (14) - Added on 2018-12-12

    This version requires Android 4.3 or newer.

    It is built and signed by F-Droid, and guaranteed to correspond to this source tarball.

    Download APK 2.1 MiB PGP Signature

    Permissions
    • android.permission.RECORD_AUDIO
    • android.permission.FOREGROUND_SERVICE
  • Version 2.2.5 (12) - Added on 2018-11-12

    This version requires Android 4.3 or newer.

    It is built and signed by F-Droid, and guaranteed to correspond to this source tarball.

    Download APK 2.1 MiB PGP Signature

    Permissions
    • android.permission.RECORD_AUDIO
    • android.permission.FOREGROUND_SERVICE
  • Version 2.2.2.3 (9) - Added on 2018-10-20

    This version requires Android 4.3 or newer.

    It is built and signed by F-Droid, and guaranteed to correspond to this source tarball.

    Download APK 2.1 MiB PGP Signature

    Permissions
    • android.permission.RECORD_AUDIO