Diadoku is a quiet logic puzzle I build on my own. The board is a grid split into color regions. Your job: one diamond in every row, column and region, and no two diamonds touching, not even at the corners. There is exactly one solution, so every move can be reasoned out.

Version 1.3 is about playing with others: in duels you race another player on the same board and earn trophies that lift you through leagues from Quartz to Diamond, with a new season every month. Boards go up to 10 x 10, and the app runs on iPad too.

Also included: a daily puzzle with streaks, a weekly star league, light and dark mode, iCloud sync. Free for iPhone and iPad.