It’s strangely fitting that one of the first handheld games to hit mass appeal, Tetris, still inspires a generation of mobile developers. Without that Russian gem we may not have mixed blessing behemoths such as Candy Crush or clever little app games such as Crobble. The brainchild of Irish developer Shane McCafferty, who also made the excellent Word Forward, Crobble mixes two of the most popular app games of all time – it’s essentially Scrabble meets Tetris. Letters rain from the top of the screen, forming a pile on the virtual floor. You must tap on letters in the right order to create words and make them disappear. When the screen fills, it’s game over. We’re used to getting apps for free, so much so that sometimes we resent upgrading, even if (as in this case) it’s €1.79. However, the tiny cost of upgrading to “Arcade”, “Zen” or “Blitz” mode is worth the price. This is an inventive, slick and hopelessly addictive app game.