Connect numbered islands with bridges so each island has exactly the right number of connections.
Each island is a circle showing a number. Bridges run only horizontally or vertically, between two islands aligned on the same row or column with no other island in between.
Tap one island to select it (it lights up). Tap a second aligned island to add a bridge. Tap the same second island again to upgrade to a double bridge. Tap once more to remove both bridges.
A pair may have at most two bridges between them. Bridges may not cross each other. The number on each island is the total count of bridges touching it — for example, a 3 must have exactly three bridges in total across its four sides.
The puzzle is solved when every island's number is satisfied and all islands form a single connected group.
Six puzzles in a row, each larger than the last. Score is total time.
Goal: clear all six in the lowest time.
Always start with the islands whose number forces them: a 1 in a corner has only two possible directions to send a bridge, and one of those is usually immediately blocked by where the other islands sit; a 4 on an edge has three sides and so must use all three; an 8 in the middle must send a double bridge in every one of its four directions. Lock those forced bridges in first, because they pin down the structure that the rest of the puzzle has to fit around.
Watch out for islands that would get cut off. A small group of islands that have already satisfied each other's numbers but aren't connected to the rest of the puzzle is a dead end — you'll have to undo bridges to reconnect them, which costs you time. When you complete an island's number, double-check that the remaining bridge budget on its neighbors still allows the larger graph to stay connected, not just the local pair.