Helps you to memorize PIN codes
About this app
Provides strategies to memorize a 4-digit PIN. Therefore it determines whether the PIN forms a T9-word, underlies a mathematical rule or forms a date or year.
It is part of the Privacy Friendly Apps developed by the SECUSO research group of the Technische Universtität Darmstadt in Germany.
Licensed under GPL-3.0-or-later, by SECUSO - Security Usability Society.
What's New in v2.0.6
Imported from the F-Droid repository index.
Version history
Jul 11, 2025 · 4.7 MB · Android API 17–34 · code 100
Imported from the F-Droid repository index.
SHA-256 d3d17402e3b40896a73365019ebdb7df6877c62bfb8cd8ac794673eec16824bf
Apr 25, 2025 · 4.7 MB · Android API 17–34 · code 10
Imported from the F-Droid repository index.
SHA-256 33537e6254f472f2408e9ccc29f30d3400698ba52a4d704a7426e0a5c142e26b
Jan 6, 2025 · 2.9 MB · Android API 17–34 · code 9
Imported from the F-Droid repository index.
SHA-256 4cc80bcf12413c55eb13e9b637670fd552e51e71174c90ecafc62f25ff4cf3d0
Will it run on your device?
73%
- Runs on a broad range of modern Android versions.
- ABI coverage is focused on newer 64-bit devices.
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.secuso.privacyfriendlypin 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, 2.0.5 is the last build before it. Android will not install an older version code over a newer one, so you must uninstall PIN Mnemonic (Privacy Friendly) 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 PIN Mnemonic (Privacy Friendly), and a listing is removed when the evidence for it stops holding up.
Get PIN Mnemonic (Privacy Friendly)
Every source we list for org.secuso.privacyfriendlypin 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
d3d17402e3b40896a73365019ebdb7df6877c62bfb8cd8ac794673eec16824bf
Signing certificate
6a20a9b62e5de8a4eafda6291e2f980ce5180daf5be0b2b8027a47713638d012
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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