Slideshot looks like a really interesting game. Yes, the lite version costs 1.99. So if you download the full version and you like it, show support for it by downloading the lite and give the devs their due reward.
Here's something in the same vein.
Bugsy
A tile sliding puzzle where you make paths for the bug (the ladybug) to get to the blooms. It's quite a challenging game.
Discussion thread is
here.
@Mew2468 -- Thanks for keeping the first page list updated.
I love puzzle games, so the sig is a way to hopefully find more of them.