Sudoku, played in color. Bubble Sudoku uses the rules you already know, with nine colorful bubbles in place of numbers 1 through 9. Every row, column, and block holds all nine colors, once each. The same sudoku logic, but color makes it feel new.

When you get stuck, the app teaches you instead of just filling the cell.

HINTS THAT TEACH
A hint names the technique that solves the cell, then explains it in plain language. Every step animates on your live board. You see which bubbles rule out which colors, and why only one can go in that cell. Hints always walk you through the easiest technique available, so you learn as you play.

15 TECHNIQUE LESSONS, AND GROWING
The library runs from Full House and Obvious Single up to Pointing Pairs, Hidden Triples, X Wing, and Swordfish. Every lesson walks through a real board one step at a time, so you can see the position before and after the move. Read them any time, not just when you are stuck.

FAIR DIFFICULTY LEVELS
Easy, Medium, Hard, and Expert are graded by the techniques a board actually requires. Every puzzle is designed to be solved using the techniques the app teaches. No board asks you to guess.

NOTHING HERE RUSHES YOU
Hide the timer and the clock leaves the board. Turn Auto Check Mistakes off and a wrong bubble will not cost you a life, so a puzzle can never end before you are ready. Sound, vibration, and the completion wave each have their own setting, so you can make the game as quiet as you want. There are no leaderboards and no other players. The only record you are up against is your own.

YOUR BOARD IS ALWAYS WAITING
Play for two minutes while you wait, or for an hour on the couch. Your board saves itself, and it is exactly where you left it when you come back. There is no account and no sign-up, and the puzzles work offline.

DAILY CHALLENGES, TROPHIES, AND BADGES
A new challenge arrives every day on the calendar. Finish a full month and you earn that month’s trophy. Badges track the rest, from your first Expert win to a perfect game solved with no hints. Every trophy and badge is drawn by hand.

SETTINGS FOR HOW YOU PLAY
Notes, Undo, and Erase. Auto Check Mistakes flags the wrong bubble as you place it, and Highlight Identical lights up every cell holding the color you picked. Two input styles: tap a cell and then a bubble, or tap a bubble and then the cells. Light and dark mode, or set it to Auto to mirror your phone. Colorblind Symbols adds a distinct symbol to every bubble color, so no move on the board depends on telling colors apart. Detailed statistics for every difficulty, so you can see where you are getting faster.

Whether this is your first sudoku or your ten-thousandth, Bubble Sudoku will leave you a little sharper. Your first puzzle is ready when you are.

Bubble Sudoku is free, with ads. Bubble Sudoku Plus is a one-time purchase that removes them and makes hints unlimited. It never expires.

Bubble Sudoku was designed and built by one person. The puzzle engine, the fifteen lessons, and every hand-drawn trophy and badge. Owned and operated by Pop Logic Studios, a one-woman studio.

WHAT IS IN THE GAME
- Nine colorful bubbles in place of the numbers one through nine
- Fifteen technique lessons, each a step-by-step walkthrough on a real board
- Hints that name the technique and animate every step
- Four difficulty levels: Easy, Medium, Hard, and Expert
- A new daily challenge, and a trophy for every month you complete
- Badges for your milestones, every one drawn by hand
- Notes, Undo, Erase, Auto Check Mistakes, and Highlight Identical
- Two input styles: cell first or bubble first
- Light and dark mode, or Auto to mirror your phone
- Colorblind Symbols, a distinct symbol on every bubble color
- Detailed statistics for every difficulty
- Hide the timer if you would rather not watch a clock
- Plays offline, with no account and no sign-up