20 logic puzzles · Android
Twenty logic puzzles on one sheet of graph paper
Sudoku, nonograms, Kakuro, Slitherlink and sixteen more — generated on the phone, checked by a solver, each with exactly one answer. Plays offline, no account needed.
from 9 November 2026
01 · Daily set
Three puzzles a day, the same for everyone
A new set starts at 00:00 UTC: three different games, from easy to hard. Solve all three to keep the streak going. Everyone on the planet gets the same puzzles — so the times are comparable.
- 3
- puzzles in a set
- 00:00
- UTC, new set
- 20
- games in rotation





02 · Catalog
All twenty games
Numbers are the same as in the app.
- 01SudokuDigits 1–N, no repeats in a row, a column or a box6×6 · 9×9
- 02NonogramNumbers say how many cells in a row are filled5×5 · 10×10 · 15×15
- 03BinairoOnly 0 and 1, never three in a row6×6 · 8×8 · 10×10 · 12×12
- 04Light UpLight every square with lamps7×7 · 10×10 · 14×14
- 05TentsOne tent beside every tree8×8 · 10×10 · 15×15
- 06BridgesJoin every island into one7×7 · 10×10 · 13×13
- 07RectanglesSplit the grid into rectangles by the numbers7×7 · 10×10 · 15×15
- 08SuguruDigits 1–N in each region, equal digits never touch6×6 · 8×8 · 10×10
- 09QueensOne queen per row, column and region7×7 · 9×9 · 11×11
- 10Star BattleTwo stars per row, column and region9×9 · 10×10
- 11SlitherlinkOne loop around the numbers7×7 · 10×10 · 13×13
- 12NumberlinkPairs of numbers, lines through every cell7×7 · 9×9 · 12×12
- 13GalaxiesSymmetric regions around their centres7×7 · 10×10 · 14×14
- 14KakuroSums across and down from digits 1–9, no repeats8×8 · 10×10 · 12×12
- 15Killer SudokuSudoku where cage sums replace the given digits6×6 · 9×9
- 16SkyscrapersHeights 1–N in every line; the numbers outside say how many towers you can see5×5 · 6×6 · 7×7
- 17FutoshikiDigits 1–N in every line; the signs between cells say which is bigger5×5 · 7×7 · 9×9
- 18HitoriShade the repeats until every row and column is clean6×6 · 8×8 · 10×10
- 19NurikabeFlood the sea around islands whose numbers give their size7×7 · 10×10 · 12×12
- 20MasyuOne loop through white and black pearls7×7 · 10×10 · 13×13
03 · Hints
A hint names the move, not just the cell
Every puzzle is solved by a step-by-step logical solver. When you are stuck, the hint shows the next deduction and its name — the same one a strong player would make.
- 01Only candidate in the cell
Every other digit already appears in this row, column or box.
- 02Only place for the digit
In this line the digit fits nowhere else.
- 03X-wing
The digit sits in the same two columns of two rows — it cannot appear elsewhere in those columns.
04 · Price
Free to play
All twenty games are free. Ads appear after a win and in the catalog — never in the middle of a puzzle. One purchase removes them for good.