Ruler (PFA)

Turns your device into a ruler.

SECUSO Research Group · org.secuso.privacyfriendlyrulerapp

Not rated yet 10K+ downloads v1.1.2 2.8 MB Android 4.2+ PEGI 3 · Everyone

Download APK 2.8 MB All versions

Same certificate as the other version checked Details

At a glance

Latest version: v1.1.2 (5)
Updated: Apr 21, 2025 (1 year ago)
APK size: 2.8 MB
Requires: Android 4.2+ (API 17)
CPU support: Any (no native code)
Category: Tools (app)
Listed since: Oct 29, 2023 (at least)
Website: secuso.org
Developer contact: [email protected]
Privacy: Developer's privacy policy

About this APK

Ruler (PFA) is an app by SECUSO Research Group in the Tools category, listed since at least October 2023. It has no native code, so it runs on any Android processor.

Since version 1.1.1, the APK grew from 2.2 MB to 2.8 MB.

What's new in v1.1.2

Updates to Android 14.

Description

From the listing uploaded by “appupdater”.

Privacy Friendly Ruler can display a ruler or protractor at the edge of the display. This enables on the fly measurements with the smartphone. It belongs to the Privacy Friendly Apps group developed by the research group SECUSO at Karlsruhe Institute of Technology. More information can be found an secuso.org/pfa/ What makes Privacy Friendly Ruler different from other similar apps? 1. No permissions Privacy Friendly Ruler does not require any permissions. 2. No advertisement Many other free apps in the Google Play Store dazzle annoying advertising and also shortens battery life. You can reach us via Twitter - @SECUSOResearch (https://twitter.com/secusoresearch) Mastodon - @SECUSO_Research@bawü.social (https://xn--baw-joa.social/@SECUSO_Research/) Job opening - https://secuso.aifb.kit.edu/english/Job_Offers_1557.php

Version history

2 versions are listed, going back to v1.1.1.

v1.1.2 LATEST Apr 21, 2025 2.8 MB TRUSTED v1.1.1 Jun 4, 2024 2.2 MB TRUSTED

All 2 versions

Security & authenticity

Security rating: Trusted

Signing certificate

Certificate issued to “Philipp Rack” Not the developer's name (“SECUSO Research Group”). Names in certificates can't be verified, so this alone proves nothing.
Same certificate as the other version checked

Store checks and file details

Developer signature verified Apr 21, 2025
Signed byCN=Philipp Rack
Signing certificate (SHA-1)CE:01:A6:12:18:B9:7A:C4:DE:AA:75:DA:4E:5A:FB:DA:05:9D:FF:20
File MD5bc1acf43395970e0089f9f7b6569dbe5
Uploaded by “appupdater” Gold tier · 117,810 followers · uploading since 2020

Scans and ratings come from the source store; the certificate comparisons are AAPKs's own, made from the files' published signatures (1 other version compared). AAPKs doesn't scan files itself — compare the MD5 and signer after downloading.

Required hardware & features

Basic touch input android.hardware.faketouch
Portrait screen android.hardware.screen.portrait

Ruler (PFA) APK: questions and answers

Can I install this APK over the version I already have?

Only if it is signed with the same certificate as the copy on your phone and isn't an older version. If Android says “App not installed”, the certificates differ; uninstalling your copy first works but deletes its data unless it is backed up.

Is the Ruler (PFA) APK safe?

No one can promise that a file is safe, but some things can be checked. The source store rates this file Trusted. It is signed with the same certificate as the other version checked. After downloading, check that the file's MD5 is bc1acf43395970e0089f9f7b6569dbe5.