Crisp and Smooth

I started playing for the points, but the rules are simple and there are no unnecessary ads (though you might watch them to get more hearts). The satisfying feeling when you clear a bunch at once is amazing. Stages you can't clear at first aren't impossible forever; after a few tries, you'll suddenly think, 'Huh? I got it!' so you don't get discouraged. It's easy and progresses smoothly, which is great.