Candy Crush is a relatively harmless, fun puzzle game which all ages can enjoy safely. However the game has been criticised for it's steep in-app purchases, and providing numerous opportunities for players to upgrade and spend money. In-app purchases shoud be restricted through your child's device before they play this game. Games of this type have also been criticised for their addictive nature - it's very easy for players (of all ages) to become completely engrossed with the engaging, repetitive gameplay and so you should ensure your child has regular time out from the app.