game-editor.com

I'm requesting the option for .dds images in the next version of GE
Although it usually requires powers of 2.. 128 x 128 256 x 256 etc
It has great loss-less compression options and would save ram on Mobile's.

The internal format used by Game Editor was designed to make the render fast.
(you can play a 900 frame animation without eat all device memory)
Using other compression format will slow down the load time.