Michal Gorny recently contacted me about his new game Shape And Hue. It's a lovely visual jigsaw puzzle.   Your task is to swap individual tiles to reveal the mosaic image. At the moment, I've solved 10 of the 100 levels.  Each level, so far, has 1 piece that's fixed - usually in the corner.  I'm guessing that's not available in later rounds. Michal made the game Hexa Knot, which I reviewed in 2018.
https://apps.apple.com/us/app/shape-and-hue/id1504053680

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