Pixlr – http://pixlr.com/
PhotoShop – http://www.photoshop.com/tools?wf=editor
Splash Up – http://www.splashup.com/
Phoenix Imaage Editor – http://advanced.aviary.com/online/image-editor
Sumo Paint – http://www.sumopaint.com/home/
Picnik – http://www.picnik.com/
Canva – https://www.canva.com/