Three rules, one solution, no guessing. Watch a full board get solved in 44 seconds, then steal the five techniques below.
The three rules
One per row, column and colourEvery row, every column and every coloured patch gets exactly one crown. That's a solved board.
Crowns never touchNot side by side, and not at the corners either. These two are too close.
Tap, tap, tapFirst tap marks a cell ✕ — "can't be a crown". Second tap places a crown, third clears it. One crown rules out a lot.
Five techniques that crack most boards
1 · Patches that fit in one lineThe pink patch lives entirely in the top row, so that row's crown has to be pink. The orange cell in the same row is out. The same goes for a patch that fits inside one column.
2 · Let every crown do its workThe moment a crown lands, cross out its row, its column, the eight cells around it and the rest of its patch. Most of a board falls to this housekeeping alone.
3 · Smallest patch firstThe pink patch here has two candidates; the green one has six. Start where the choices are fewest and work outwards.
4 · Two patches, two linesPink and orange both fit inside the first two columns, so those two columns' crowns are theirs. Every other patch loses its cells there — here, the two green ones.
5 · The cell that kills a patchA crown on either ✕ would touch both pink cells and leave pink with nowhere to go. So neither can be a crown — before you know anything else.