Audio Signal Generator
About this app
Audio signal generator with twirly knob.
The frequency knob responds to finger twirling. The fine frequency and level sliders allow for fine adjustments of frequency and output level. The frequency knob is also adjustable using the left and right arrow buttons. The two bookmark buttons below the frequency knob show if there are bookmarks, and will go to the next lower or higher bookmark if it exists.
* Frequency range 0.1Hz - 25KHz * Level range 0dB - -80dB * Set exact frequency * Frequency bookmarks
Licensed under GPL-3.0-only, by Bill Farmer.
What's New in v1.37
Imported from the F-Droid repository index.
- * Use executor for background tasks
- * Update SDK, build tools
Version history
Mar 27, 2026 · 0.1 MB · Android API 23–35 · code 137
Imported from the F-Droid repository index.
- * Use executor for background tasks
- * Update SDK, build tools
SHA-256 e2cad1884047d80856141432169baaf9313722188ef5881e9c2a15d78b1d3601
Nov 24, 2023 · 0.1 MB · Android API 23–31 · code 136
Imported from the F-Droid repository index.
- * Add Simplified Chinese translation
SHA-256 436941b0de573719c400737d6ff7867bbf218d1c6349afdc9bd65d97ab685f05
Nov 11, 2023 · 0.1 MB · Android API 21–31 · code 135
Imported from the F-Droid repository index.
- * Update icons
SHA-256 564757bb718f6da236e3e26d38dbb10b1524f03d904288f3fc95d8ff702778e5
Will it run on your device?
78%
- Runs on a broad range of modern Android versions.
- ABI coverage is focused on newer 64-bit devices.
- Aligned with the latest Android target SDK expectations.
Installation Guide
Open Settings on your Android device
Go to Security → Unknown sources (or Install unknown apps)
Enable "Allow from this source" for your browser or file manager
Open the downloaded APK file from your Downloads folder
Tap "Install" and wait for installation to complete
Launch the app from your home screen
Make sure to re-enable Unknown Sources restrictions after installation for security.
How to install this safely
How to verify the file you downloaded
Before you install anything, confirm the file is the one described here. On a computer, run shasum -a 256 your-download.apk (macOS or Linux) or certutil -hashfile your-download.apk SHA256 (Windows), then compare the output character-for-character with the SHA-256 on this page. If a single character differs, the file is not the build we recorded — delete it.
What the signing certificate proves
Every Android app is signed with a private key that only its developer holds. The fingerprint on this page is a hash of the matching public certificate, and it proves continuity rather than identity: it tells you a build came from whoever signed the earlier ones. Android enforces this at install time — if a package claiming to be org.billthefarmer.siggen is signed with a different key, the system will refuse to install it over your existing copy. A fingerprint that changes between releases is worth pausing on, because a repackaged app that has been modified by someone else cannot keep the original signature.
How to roll back to an earlier version
If the current release misbehaves, 1.36 is the last build before it. Android will not install an older version code over a newer one, so you must uninstall Signal Generator first — which clears its local data unless you have a backup. Reinstall the older APK only if its signing fingerprint matches the build you already trust, and check the API range: an older release may target an Android version your device has moved past.
Why we list sources instead of hosting everything
The official store channel is almost always the right choice: it updates automatically and carries the publisher's own distribution guarantees. A direct APK is useful when a device has no store access, when a rollout has not reached your region, or when you need a specific version — and only when the publisher has authorized that copy. APKBrowse does not list pirated, cracked, or unauthorized rebuilds of Signal Generator, and a listing is removed when the evidence for it stops holding up.
Get Signal Generator
Every source we list for org.billthefarmer.siggen is legality-reviewed. Pirated or cracked builds are never offered.
Other sources
F-Droid listing
officialF-Droid builds this app from source and signs it. This is its official listing, with older builds and full release notes.
Source code
verified publisherThe upstream repository this build is compiled from.
We check legality and signature continuity, but device behaviour still varies. Install at your own discretion.
App Information
Security Verification
We record provenance; we do not run malware scans. Verify the hash yourself before installing.
SHA-256 Hash
e2cad1884047d80856141432169baaf9313722188ef5881e9c2a15d78b1d3601
Signing certificate
8934bbf44d2a887269278bc7640e0385728bcec49eb901dd2262f519a24b54c0
Permissions Required
What each permission lets Signal Generator do. A highlighted one is worth a second look — not necessarily wrong, just worth asking whether this app needs it.
Previous Versions
The signing certificate fingerprint for this release is on record, so a build that does not match it did not come from this publisher.
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