Rangku Alu

Count the Beat

Free · In‑App Purchases · Designed for iPad. Not verified for macOS.

The bamboo poles clap shut on a beat. Find every beat they stay open — and jump in. The bamboo poles clap shut on a beat. Your job is to work out which beats they stay OPEN, tap every one of them, and jump. That is multiples, wearing bamboo. If the poles shut every 3rd beat, the safe ones are the beats that are not multiples of 3. Add a second pair on its own cycle and the safe beats become the ones that are multiples of neither — common multiples, discovered rather than recited. Nothing here is graded on reaction speed. You choose your beats first, then watch it play out, so a slower child is never at a disadvantage and two players are always judged on the same arithmetic. • Watch & Count — every 2nd beat • Skip It — 3s, 4s and 5s • Two Pairs — multiples of neither • Cross the Grid — shifted beats Solo is unhurried practice: puzzles keep coming, you can retry any one until it clicks, and the stars you earn stay banked for each world. vs Tokek is a match — the gecko commits at the same moment you do, and you watch it jump in beside you and get caught, so you see exactly which beat it misjudged. Or hand the device to another player: same puzzle, no peeking, best of three. Free to play World 1, all two-player and Tokek. One purchase unlocks the rest, once. No ads, no subscriptions, no accounts, no data collected, ever. Fully offline. 11 languages with proper right-to-left for Arabic and Urdu. Ages 4+. About the game: rangku alu is played by children in Manggarai, on the island of Flores in East Nusa Tenggara, Indonesia, after the rice harvest — the poles are alu, the pestles used to pound rice. In the real game the beat is felt, not counted. Counting it is our idea, to make the arithmetic visible.

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    Information

    Seller
    Phuc Huynh
    Size
    5.2 MB
    Category
    Education
    Compatibility
    Requires iOS 15.0 or later.
    • iPhone
      Requires iOS 15.0 or later.
    • iPad
      Requires iPadOS 15.0 or later.
    • iPod touch
      Requires iOS 15.0 or later.
    • Mac
      Requires macOS 12.0 or later and a Mac with Apple M1 chip or later.
    • Apple Vision
      Requires visionOS 1.0 or later.
    Languages
    English
    Age Rating
    4+
    In-App Purchases
    Yes
    Copyright
    © 2026 Phuc Huynh
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