Is DumberKit: Calculator safe?

A calculator and unit converter for keypad phones like the Qin F21, Dumber Mini or Doov R77 Pro. There are no on-screen buttons: you type the calculation straight on the keypad and press OK for the result. Touch is switched off inside the app, so nothing gets pressed by accident in your pocket. Keys • 0–9 – type numbers • – add an operator, press it again for the next one (+ − × ÷) • Hold – a pal…

Developer: lbockaj
Category: Calculator
Earliest archived version: 14 Oct 2026
License: GPL-3.0-only (per F-Droid metadata)

02 / Release notes

Release notes from F-Droid

14 Oct 2026

1.0.0

First release: calculations typed straight on the keypad with the usual order of operations, a symbol palette on a held, a history you can go through with up / down, and the unit converter and settings in tabs switched with left / right.

Full notes →

03 / Package identity

Technical fingerprint

Application IDcom.dumberkit.calculator

Latest APK SHA-2562b0d5b63c48405ded8c4e803fbcc9432262c8c3cf53d6c95fd96bb457ae67671

Signing certificate4B:80:91:26:AB:6D:8F:4C:4A:04:A0:51:49:44:B2:0A:93:13:DD:C9:A3:3B:83:0F:6A:42:07:A9:91:C8:80:9B

MIN ANDROID26TARGET36ARCHITECTUREarm64-v8a · armeabi-v7a · x86 · x86_64

04 / Version archive

Documented releases

1 TOTAL

VersionReleasedAndroidArchitecture

1.0.014 Oct 202626+arm64-v8a, armeabi-v7a, x86, x86_64→

05 / Safety & access

Safety verdict

Authentic — file hash matches the source indexNo ads or tracking flagged by the source

IntegritySHA-256 verified vs source

SourceOpen-source · fdroid

Permissions1 declared · 0 sensitive

Signaturepresent

Anti-featuresNo known anti-features

Sensitive accessNo sensitive permissions

Declared permissions

org.fossify.android.permission.WRITE_GLOBAL_SETTINGS

Tracker status: Not assessed by WIKI for Android.

06 / Sources

Evidence ledger

Each entry is a captured public reference backing this record.

RepositorySource package page↗Source codeSource repository↗