sudokyu。

sudokyu。 is the classic number puzzle in a softer world.

fill the grid so every row, column and 3×3 box holds 1 to 9. finish all nine of a digit and kyu — a small nine-tailed fox — grows a tail. all nine tails: solved.

✿ the puzzles
• four difficulties, from easy to very hard, made fresh on your phone
• every puzzle has exactly one solution
• graded by the techniques it needs, so very hard means x-wings, never guessing
• a new daily puzzle every day, the same for everyone
• relaxed, timer or countdown: play without a clock, chase the suggested time, or race it

✿ gentle tools
• notes for pencil marks, undo and redo, erase
• hints that explain why: "7 has just one home in this box"
• optional mistake highlighting, plus matching-number and row/column highlights
• your puzzle saves as you go

✿ every solve, a time-lapse
watch your whole solve replay in seconds, then save it as a vertical video to share.

✿ collect
• 64 trophies, levels and daily streaks
• best times and stats for every difficulty

✿ themes
sakura and yozakura are free. five theme packs add four themes each — universe, kawaii, seasons, tea time and magical forest — each with its own colors, weather and an outfit for kyu. buy packs one at a time or all five together. one-time purchases, no subscription.

✿ quiet by design
no ads. no account. no tracking. your progress stays on your phone.