Soo... I've created this character in Assembly(app) and.. Now I'm experimenting with several animation apps to animate it.
Theres an app called Plastic that allows you to rig your own characters and animate them.
The way Plastic works is that it deforms the image based on the influence of each bone you draw on it.
Anyway.. Heres an animation i exported. It actually tweens between keyframes for a smooth result.
To export this as transparent png's you'll need to upload them to dropbox ($3.99 feature)