Play your favorite Categories game, as a standard app or right in your messages! Challenge your friends, take advantage of new iOS 10 stickers and animations features, and have fun. How to launch an iMessage app Go into an iMessage conversation, click the A icon (or the arrow icon if it is not displayed). If you play for the first time, click the bottom left corner button to display your messages extensions and click the Categories icon to start a new game. For any question or suggestion, please send us an email at [email protected].