Think. Solve.
Repeat.
The classic number puzzle, tuned for your phone. Three difficulties, four themes, and a board that never asks you to wait for an ad between rounds.
Play your way
Four built-in looks — switch anytime, mid-puzzle, no restart needed.
Start relaxed, finish sharp
Every puzzle is generated fresh — pick a level by how many givens you want to lean on.
Easy
Relaxed pace, plenty of starting numbers. Good for a coffee-break round.
Normal
Balanced logic puzzles that still move quickly once you find a rhythm.
Expert
Real challenge — fewer clues, more deduction, for when you want to focus.
Everything a good puzzle needs
Nothing you don't need — just the tools that make solving comfortable.
Pencil notes
Mark candidate numbers in any cell so you can think a few moves ahead without losing your place.
Undo & erase
Take back a move or clear a cell in one tap — mistakes stay easy to fix, not costly to make.
Mistake tracking
See where you've slipped up as you go, instead of finding out at the very end.
Smart hints
Stuck on a cell? A hint nudges you forward without solving the whole puzzle for you.
Win streaks
Every completed board is a small win — build a streak across easy, normal, and expert.
Share a puzzle
Found a good one? Send it to a friend and see who finishes first.
Your next puzzle is one tap away
Free to play. Works offline. No sign-up required.