Microsoft Corporation is working on bringing one-hand keyboard to iOS devices. This feature called Word Flow is now available at Windows 10 Mobile platform.
Although the Windows 10 Mobile keyboard also has a one-handed mode, iOS version is expected to be different. Microsoft's Windows 10 Mobile keyboard simply shifts to the side creating a compact keyboard, while key layout for iOS comes in the shape of fan. The one-handed mode works on each side, allowing using either right or left hand to swipe letters or type.
As for the rest Word Flow for iOS is very similar to the Windows Mobile version. There are word suggestions, emoji and swipe letters available. Microsoft is planning to launch Word Flow to iOS in the coming months and Android version expected later this year.