"Threes! may not look like much at first sight, but it's actually one of the more potent, more addictive games for tablets and smartphones that's now been ported to Xbox One. The concept is simple — you basically make big numbers by adding up smaller numbers; 3+3 makes 6 and so it goes.
The game is based around a board consisting of 16 tiles. You're supposed to create as many large numbers as possible, matching two tiles of the same value together by swiping them into each other. Doing this creates a single new tile with a higher value and, of course, the higher the tile number on your board, the higher the end score. Each time you swipe numbers, a new tile is placed on the board."