I use Snapseed on Android. It's a practical app with many photo editing tools
I like how I can edit my photos here,
Hugin - Hugin is an easy to use cross-platform panoramic imaging toolchain based on Panorama Tools.
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 .
Stitch Panorama - Stich Panorama is a plug-in for the GNU Image Manipulation Program (GIMP) which takes digital...
PicsArt - Explore 100,000,000+ awesome images and photos on the web
TrinusVR - TrinusVR connects your Android phone to your PC so you can play your PC games in virtual reality.
Pixelmator - Pixelmator is an image-editing application for Mac and iPad.