ThinkSync Puzzles

Sudoku brain training at 40 Hz

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

Free for 7 days, everything unlocked. After that: three puzzles a day, or unlock all of it once and keep it forever. No subscription. Your brain works in rhythms. ThinkSync puts one behind the puzzle. Sudoku is thinking you actually enjoy — you hold nine numbers in your head, test a guess, take it back. ThinkSync adds a rhythm to it: while you solve, light and sound pulse forty times a second. You hear it and you see it. If it distracts you, switch it off and keep playing. The puzzle stands on its own. THE 40 HZ RHYTHM Rhythmic light and sound in the gamma band around 40 Hz is studied at MIT and elsewhere. There are research findings suggesting that such stimulation influences gamma activity in the brain. What that activity means for attention and memory is still being studied — and we link the papers, including the ones that found nothing. BRING YOUR OWN MUSIC Start Spotify or Apple Music, then start a puzzle. ThinkSync layers its stimulation over whatever is playing, and a slider lets you decide how present it should be. Nothing is interrupted and nothing is taken over. THE PUZZLES Four levels, from easy to expert, each generated fresh and each with exactly one solution. Nothing is downloaded and nothing repeats. A new Puzzle of the Day every morning, the same one for everyone. Mondays start gently and Sundays are for experts. A calendar shows the days you have finished. TRAIN, AND SEE IT Nineteen trophies, from your first solved puzzle to a flawless run without a single mistake or hint. Best times per level. Your streak counts days, not puzzles — solve one a day and it keeps going. A game in progress survives closing the app. Come back tomorrow and the grid is exactly where you left it. BUILT PLAINLY No account. No tracking. No ads. No network connection of any kind — everything happens on your device, and everything works in flight mode. WHAT IT COSTS Seven days with everything unlocked. After that you keep three puzzles a day and the Puzzle of the Day for free, or you unlock everything once, for a single payment. No subscription, no renewal. PLEASE NOTE ThinkSync is a game. It is not a medical device and does not replace therapy or medical treatment. Flickering light can trigger seizures in people with photosensitive epilepsy — if that applies to you, leave the light off. The switch is right in the setup, before the first pulse.

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    Information

    Seller
    CHRISTIAN PETER
    Size
    1.6 MB
    Category
    Puzzle
    Compatibility
    Requires iOS 16.0 or later.
    • iPhone
      Requires iOS 16.0 or later.
    • iPad
      Requires iPadOS 16.0 or later.
    • Mac
      Requires macOS 13.0 or later and a Mac with Apple M1 chip or later.
    • Apple Vision
      Requires visionOS 1.0 or later.
    Languages
    English and 2 more
    • English, German, Spanish
    Age Rating
    9+
    In-App Purchases
    Yes
    Copyright
    © 2026 Christian Peter
  • Developer Website
  • Privacy Policy

    • Supports

    • Family Sharing

      Some in-app purchases and subscriptions may be shareable with your family group when Family Sharing is enabled. Learn More

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