Continuing with the one row keyboard patent app.....
reading it I see a few more details
The option is left open for the keyboard to be a flip out attached accessory or slide out also instead of just fixed.
One of the keyboard buttons is for cycling through predictive text selections.
To switch from numbers to letters you press two keys at the same time.
They also show it curved and used on a phone handset
They call it a phone but it looks like a tablet to me.
It has a dpad, options and clear button next to the screen.