Daily logic puzzle
One tap.
A whole line.
Each stroke marks a row, column or diagonal. Read the lines, plan your taps and darken every square.
3 × 3 and 4 × 4 to start. Optional in-app unlock.
The idea is simple
Read the line.
Change the board.
- 01
Read the strokes
Each stroke marks a complete row, column or diagonal. It tells you which line will change.
- 02
Make your move
Tap a square to switch the indicated lines between light and dark. Use Undo to explore another possibility.
- 03
Leave every square dark
That is the goal. Once you solve the board, see whether you can find a solution with fewer taps.
A closer look
A clear board.
Room to explore.
Follow your progress, try a smaller grid and return to the puzzles available in your calendar.
Start with the daily puzzle
Your next challenge,
at your own pace.
Begin with the smaller boards. If you want more space to think, the optional unlock opens larger grids and the full calendar.
Start playing
- Daily puzzle
- 3 × 3 and 4 × 4 boards
- Recent puzzles
- Undo a move
Explore further
- 5 × 5 and 6 × 6 boards
- Full calendar access
- More room for your strategy
Larger boards and full calendar access require an in-app purchase.
A few useful answers
Before your
first tap.
What is the goal?
Darken every square. Each stroke shows a complete row, column or diagonal that changes when you tap.
Can I undo a move?
Yes. Use Undo to return to the previous board and explore a different sequence.
What does the optional unlock include?
The 5 × 5 and 6 × 6 boards and full calendar access are unlocked with an in-app purchase. Start with the daily puzzle and 3 × 3 or 4 × 4 boards.
Can I return to earlier puzzles?
Choose an available date in the calendar to revisit its puzzle. Full calendar access requires the optional unlock.
EKIS for iOS and Android
One board.
Where will you start?
Same goal. Different rules.
DEKIS: Follow the arrows. Change the neighbouring squares.