Daily
One puzzle a day, the same for everyone — generated deterministically from the date so the difficulty curve is shared.
Sumi
A quiet sudoku practice.
Ink on paper. Nothing in the way. Sumi is a daily Sudoku app designed around stillness. No leaderboards, no nagging notifications, no celebration confetti. Just the grid, warm paper underneath, and the quiet satisfaction of placing the last number.
Empty space is not empty. It is waiting.House, Sumi quote book
Stillness
No leaderboards, no nagging notifications, no "you broke your record!" overlays. Skip a day, skip a week — the puzzle waits.
Record
Quiet stats. Personal bests by difficulty, an improvement curve, a calendar of the days you played. Nothing more.
Aesthetic
Warm washi paper, soft ink tones, an editorial serif typeface, and Japanese typographic accents. Sudoku as it should look.
5
3
7
6
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9
8
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7
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9
5
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3
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6
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8
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4
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7
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6
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8
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3
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2
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3
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1
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6
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6
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4
1
9
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8
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2
8
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5
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7
9
A puzzle in progress. Given numbers in ink; your numbers in fountain-pen teal.
Sumi tints itself to the calendar. Sakura, leaf, maple, and snow — the petals know what month it is.
Free, with an optional one-time purchase to unlock the full game.