I use Snapseed on Android. It's a practical app with many photo editing tools
I like how I can edit my photos here,
VSCO - VSCO® is an art and technology company empowering people everywhere to create, discover, and connect. CompanyVSCO® is a trendsetting art and technology company that .
Smoothboard Air - Smoothboard Air is a collaborative interactive whiteboard application for iPads and Android devices that revolutionizes interaction in lecture rooms.
PicsArt - Explore 100,000,000+ awesome images and photos on the web
Groupboard - Free collaborative online whiteboard, web conferencing and online tutoring software that can be embedded in your own website. Used by many online tutors, schools and universities.
Pixelmator - Pixelmator is an image-editing application for Mac and iPad.
RealtimeBoard - RealtimeBoard is an online collaboration software created as a team collaboration and online brainstorming tool. It's super easy to use & free!