I use Snapseed on Android. It's a practical app with many photo editing tools
I like how I can edit my photos here,
GoldenHour.One - Your personal assistant for outdoor photography for iOS
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 .
Retinize It - Photoshop actions for preparing designs for iOS or optimize
PicsArt - Explore 100,000,000+ awesome images and photos on the web
CSS Hat - Turn layers from Photoshop CC 2014 to code instantly.
Pixelmator - Pixelmator is an image-editing application for Mac and iPad.