Is Mental Math safe?

"Mental Math" is a simple and clean Android app for mental arithmetic training. You can practice on your own or challenge friends to compete and improve your skills. The app is open source and respects your privacy. Customizable Training Select which arithmetic operations to include (+, −, ×, ÷). For each operation, choose from nine difficulty levels to customize your training precisely to your s…

Developer: HeldDerTierwelt
Category: Educational Game
Earliest archived version: 19 Aug 2026
License: GPL-3.0-only (per F-Droid metadata)

02 / Release notes

Release notes from F-Droid

27 Sept 2026

Added sound as a feedback option. - Added vibration as a feedback option. - Reorganized the menu with expandable categories for a more structured layout. - Added Arabic translation contributed by Eisa Ali and E Ta. Thank you!:) - Previous game settings are now preserved after Random Game or Link…

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19 Aug 2026

Reorganized strings.xml files to enable translations via Weblate ( - Added Bengali translation contributed by Mahir Daiyan. Thank you!:) - Added Hungarian translation reviewed by Dóry. Thank you!:) - Added Serbian translation reviewed by Svetislav. Thank you!:) - Added Croatian translation reviewed…

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03 / Package identity

Technical fingerprint

Application IDcom.helddertierwelt.mentalmath

Latest APK SHA-25633f716618cf8a3f9d070689103a586e8739e1a608e52c7584d20aed53da1f6ae

Signing certificateDE:19:7B:4C:F2:B8:58:80:E0:21:11:59:B6:0B:6E:3C:39:F9:6F:F0:68:68:AE:48:39:C4:2D:8A:4D:6F:3F:E5

MIN ANDROID24TARGET36ARCHITECTUREarm64-v8a · armeabi-v7a · x86 · x86_64

04 / History

Archive history

2 versions in WIKI archive: earliest 27 (19 Aug 2026), latest 28 (27 Sept 2026).

Permissions changed between 27 and 28: added android.permission.VIBRATE.

05 / Version archive

Documented releases

2 TOTAL

VersionReleasedAndroidArchitecture

2827 Sept 202624+arm64-v8a, armeabi-v7a, x86, x86_64→2719 Aug 202624+arm64-v8a, armeabi-v7a, x86, x86_64→

06 / 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

Permissions5 declared · 0 sensitive

Signaturepresent

Anti-featuresNo known anti-features

Sensitive accessNo sensitive permissions

Declared permissions

android.permission.POST_NOTIFICATIONS android.permission.RECEIVE_BOOT_COMPLETED android.permission.VIBRATE android.permission.WAKE_LOCK com.helddertierwelt.mentalmath.DYNAMIC_RECEIVER_NOT_EXPORTED_PERMISSION

Tracker status: Not assessed by WIKI for Android.

07 / Sources

Evidence ledger

Each entry is a captured public reference backing this record.

RepositorySource package page↗Source codeSource repository↗