This game is fun & challenging but it is very difficult to adv w/o spending money to get gems. The gems allow you buy boosters. The boosters are the only way for you to beat levels once you get past level 20. The do hv an option to watch videos to get gems, but you only get 2 gems per video & it costs 100 gems to buy a set of 3 boosters. Plus you hv to watch a video ea time you play a level. You can't move to a new level until you get a key which will allow you to move to the next restaurant.