Gboard - Google-powered keyboard with search, GIFs, emojis and more!
Grammarly Keyboard - If you want your mobile writing to truly shine with its polish, you need the Grammarly Keyboard
Emoji Keyboard - Allows searching and inserting into other applications near thousand emojis.
Hacker's Keyboard - Are you missing the key layout you're used to from your computer when using an Android device?
Swiftkey - SwiftKey keyboard allows for seamless typing and adapts to the way you type, so you can spend less time correcting typos and more time saying what you mean.
CozyKey Pro - CozyKey is an intuitive iPhone keyboard for fat fingers.