Huetopia by ZealTopia Interactive $.99

 Huetopia comes from ZealTopia.  It's a shunting puzzle.  The object is to pivot the individual pieces so that the circles lie on a matching area. Pieces can only be rotated in a clockwise manner. They can also slide forward and back.

I contacted Eko Mirhard who is the brain behind Huetopia.  According to him, there are 99 levels. I've done 77 levels, which is more than enough. This game is hard!

Zealtopia also made Noda which I liked.

https://itunes.apple.com/us/app/huetopia/id1145920150?mt=8
http://www.zealtopia.com/