If we are running out of keys for characters, we can also have 2 special "modifier" keys, behind the keyboard You know, the place where our index finger would be, when we are thumb typing! The best example would the L1 & R1 buttons on PS3/PS4 controllers http://cdn.gidn.net/images/stock/con..._diagram_2.jpg, With that we should be able to add around 80 more characters!