Color Rings! comes from Sphere Game Studios. We've seen this type of game in the past several times, but not in a while.  The object is to tap on any ring, which will fire 1 missile in each direction, setting off a chain reaction.
The red rings need to be hit once.
The orange rings need to be hit twice.
Yellow 3 times Green 4 times.
Purple 5 times.

The essential point in this puzzle is which rings to tap. Then do trial and error. 

There are 100 levels.  I did the first 25 in about 10 minutes. I'm around level 40 now.https://itunes.apple.com/us/app/color-rings/id1448795214"mt=8

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