Optimage - Advanced image optimization tool
Pixlr - Pixlr® makes it easy to transform everyday images into stunning works of art.
ImageOptim API - Web service for image compression
Priime - Edit photos with the styles of the world's top photographers. Smart suggestions, fast editing, and inspiring collections.
Imagify - Optimize and resize images online and through your CMS.
PicsArt - Explore 100,000,000+ awesome images and photos on the web