You know the famous logic puzzle about using a boat to get a wolf, goat, and a head of lettuce across a river, right? Well, in Puzzle Land, this is only the beginning of what you might be asked to transport from one bank to the other. River Tests Pro provides eight such logic problems for iOS, with more puzzles coming — and right now the app is free. (Alas, the app dpesn’t provide the wolf-goat puzzle with an alternative solution.)