upon playing Twice! it seems our scepticism was ill founded as though the concept may sound a bit bland, the game succeeds in being an enjoyable puzzler and has a good stab at living up to HeroCraft's claim that it's an effective memory training tool.
You start with a grid and can uncover up to three blocks at a time. If you make a match, the pair remain exposed; if you fail to make a match, your available number of tries reduces by one. Fail to match every pair in the grid before you run out of tries, you lose a life and have to start again. As you progress, the grids get increasingly bigger and comprise different shapes.