Does ios7 support third-party software keyboards?
Whether they were removed after an App Store rules update I don't know, but one of the first apps I ever downloaded was a 3rd party keyboard called Swype.  The difference between it (&amp; others that were or may still be around) is that it cannot be plugged in in the same way as on Android, and become the default keyboard for all text input system wide, and instead runs as a standalone app that you can use to type stuff, then copy, then paste into wherever you want it to go using the normal iOS keyboard.

In addition, many apps augment the standard keyboard with a customised top row, made to look like it's part of the keyboard when in fact it's just an extra bit within the app, rather than on the keyboard - these are typically used to allow for extra keyboard functions like word left/right, or to provide quick access to common symbols like # or @ etc.

No formal announcement has been made about an official replacement API, and I would not expect to see one any time soon, as it goes against the whole "tinker proof" direction that iOS has always walked.