If you're looking to fill a little corner of your day playing with your phone, then turning to a puzzle game is probably a safe bet.There are plenty to choose from and it's often the simplest of games that draw you in. Today we're looking at something that's straight forward, almost a throwback to the sort of thing you'd find in your Christmas stocking as a kid.Shift It\nFormat\nAndroid\nPrice\nFree\nWhere\nGoogle Play\nShift It is a simple game that involves moving tiles around a board. The aim of the game is to group the colours together in as few moves as possible to complete the level.Each level remains locked, so you have to have some success before you can progress, with more than 300 levels to get through and different sizes of boards to play on.There are a number of different gameplay elements to add variety, with various blocks that behave in different ways so that things don't get samey too quickly.To help you along there is a hints system, although really a game like this is about sitting, staring, scratching your head and getting on with it. That's because if you use the trial and error approach, you'll clock up more moves and get fewer stars when you finish.\u00a0Collecting those stars is important, because to progress to the larger grids you'll have to accumulate a specific number. You can unlock levels without getting the right number of stars, but you'll have to pay for the privilege.Like many games, Shift It contains advertising that isn't too intrusive, but sometimes includes full-page adverts for other games, as well as the in-app purchase options.But we're happy to overlook that, because Shift It is fun and addictive and although it's so simple, with big bright colours, it can still be amazingly frustrating.