Sudoku that fits in one hand.
Play a full game of sudoku with one thumb. Standing on the train, holding a coffee, or lying in bed with the phone above your face.
The board sits at the top of your screen, untouched. All your input happens in a strip at the bottom, right where your thumb already rests. Drag along it and a cursor walks the grid, with a small haptic click at every cell edge, so you always know where you are without looking down.
The first five levels are free, so you can find out whether one-handed play suits you before paying for anything. One payment of $3.99 unlocks the rest: 50 puzzles in all, hand-verified across five difficulties, plus the packs added in later updates. Not a subscription.
Every puzzle has exactly one solution and can be solved by pure logic. No ads. No account. Nothing leaves your phone, because the app has no network code at all.
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