Developer Steven Troughton-Smith made the discovery early this morning, tweeting, "Also new in iOS 9 - UIKeyboard seems to scale to a much larger heretofore unseen iPad screen size #ipadproconfirmed".
The larger keyboard adds a fifth row of keys, as well as tab and caps lock keys on the left side. It's layout is more similar to a hardware keyboard with bigger keys in traditional locations.
Alongside the new keyboard, iOS 9 also brings new Slide Over, Split View, and Picture-in-Picture multitasking features which would making working on a larger iPad Pro much more productive.
Apple is expected to release the new tablet this fall but for now you can check out images of the keyboard below.
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