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CLUSTER MENTAL-TIMED-ARITHMETIC · 10 ENTRIES · EARLIEST ENTRY 2012-11-13

Mental arithmetic training apps

This cluster consists of apps and web tools for timed mental arithmetic practice, including multiplication drills, Soroban abacus training, and calendar-date calculation. The dated history shows entries in 2012, 2017, 2020, 2022, 2023, 2025 (twice), and 2026, indicating sporadic releases with no clear trend. Traction is low across the board, with Mental Math, math-practice-app, and Afri-Soro all at 0 stars, so no single product leads.

Entry timeline

ENTRY TIMELINE

NOV 2012: 1DEC 2017: 1AUG 2020: 1JUL 2022: 1MAR 2023: 1NOV 2025: 1MAY 2026: 1AUG 2026: 2OCT 2026: 1
NOV 2012OCT 2026

Each bar is the month a member carries, which is a creation date where the source published one and a crawl date otherwise. Nothing in the index was found before 11 August 2026, and coverage broadened sharply on 14–15 August, so a bar from then on reports how much we found that month, not how much was built; an earlier bar reports how far back a member's own source dated it — not how long we have been watching.

Members by activity

Activity signals, not revenue.

Build origin · 3 hand-coded · 7 unlabelled

Operator · 2 hobby · 2 commercial · 5 open source · 1 unlabelled

Two labels per entry, never collapsed into one: how it was built, and who stands behind it. Counted over the 10 listed below. Unlabelled means nothing has decided yet — not that the answer is small.

  1. 01Mathe-Trainer0★14 dayslivehand-codedopen sourceGerman-language education app that trains primary school children in mental arithmetic through timed lessons and rewards, with parental controls and local leaderboards.
  2. 02Mental Math0★20 daysliveopen sourceAndroid app for practicing mental arithmetic with customizable difficulty, timed modes, and friend challenges through shared links.
  3. 03math-practice-app0★23 days—hand-codedhobbyA mobile app for practicing timed mental math with adjustable difficulty and a countdown timer.
  4. 04mental-math0★1 molivehobbyWeb app that drills users on mental math with timed multiple-choice questions by category and difficulty and tracks accuracy and speed over time.
  5. 05Math Brain Booster Games0★4 molivecommercialMath training app with timed arithmetic drills to improve concentration and mental agility.
  6. 06Calculate0★1 yrabandonedliveopen sourceMental arithmetic training app with configurable tasks, statistics, multi-user support, and timed trial mode.
  7. 07Quick Calculation0★1 yrstaleliveopen sourceApp that offers timed arithmetic practice exercises with customizable ranges to improve mental calculation speed.
  8. 08Multiplication Flash Cards 4th0★2 yrabandonedlivecommercialSpaced repetition app for mastering multiplication facts through short, adaptive practice sessions.
  9. 09Guessaday0★8 yrabandonedlivehand-codedopen sourceTraining app that quizzes users on the weekday of a random date, optionally timing responses to improve mental calculation.
  10. 10Countdown Number Round Tree Solver0★unknownliveWeb app that solves Countdown number puzzles by computing arithmetic expressions to reach a target from given digits.

Ranked by traction, highest first, and paged 20 at a time — this is a window on the cluster, never the whole of it. Ties are broken by a stable id so a product cannot appear on two pages or fall between them. Browse every cluster.