Choose a shape, tap the board to preview, then place it.
Find a fit previews a legal suggestion; you still choose whether to place it. Score = squares placed.
How the commons works
Start in your marked corner. After that, every new piece must touch your colour at a corner. Your pieces must never share an edge. Other colours may touch freely.
Each colour has the same 21 shapes, worth 89 squares. Rotate and flip them freely. When no shape fits, your turn passes. Most squares placed wins; tied scores share the win. No completion bonuses.
Solo: you are Jade, three local computers take the other colours. Table mode: four people share this device. Progress saves here automatically.
Keyboard: focus the board, use arrows to position, R to rotate, F to flip and Enter to place. Buttons also work with Tab and Enter.