Microsoft has just released their new Free Word Flow Keyboard for iPhone users.
The free keyboard app is only available on iOS App Store in the United States.
The keyboard app can be used like a traditional keyboard but when you are feeling a bit lazy and want to type with only your thumb, it can be switched into an arc mode which then allows you to swipe between letters and form words and sentences quickly using only your thumb.
The arc mode can be adjusted for left or right handed users. The app is already seeing a lot of success with iPhone users and it will soon be released worldwide.