TypingMaster - Learn touch-typing technique, and improve/increase typing accuracy and speed.
Gboard - Google-powered keyboard with search, GIFs, emojis and more!
amphetype - Advanced typing practice program
Fleksy - Fleksy is the #1 private, white-label virtual keyboard SDK, enabling companies to create unimaginable products.
Type Fu - Type Fu is an app that will teach you how to type fast. The right way. On Mac, Windows and Chrome OS.
AnySoftKeyboard - Android (f/w 1.5+) on-screen keyboard for multiple languages.