What's a good iOS game for challenging shape-based puzzles?

If you're looking for a stimulating shape-based puzzle game on iOS, Flow Free: Shapes is an excellent choice. It builds upon the original Flow Free concept by incorporating different shapes, adding a layer of complexity and challenge. The game presents a satisfying mental workout as you connect matching shapes without crossing paths. The increasing difficulty levels ensure that you'll always have new and engaging puzzles to solve, keeping you entertained for hours. It's a great game to play anywhere at any time. The game is easy to pick up but hard to master, providing a rewarding experience for puzzle enthusiasts of all skill levels.