This is a experiment, after choosing an image you will see a Add Jim button, click that, and then click the Make Gif button that appears. A still image will appear on the left followed by a gif on the right after a short delay (mobile is a bit slower).
Just uses the image as background, 1st frame of gif, so no background animation.
Everything happens in your browser. Not working here in Firefox, Chrome & Safari work for me, I've only tried IE9 on a pc and the file upload fails there. No error checking we codejam econo;-)
The Square Jim is a start/test
Not sure why I get some black frames esp on iOS? fixed
The Jim gif from Talky Tina.