A method from pocket pc
I've tried using this: http://www.spbsoftwarehouse.com/products/fsk/screenshots.html
It works quite well. EsbenDamgaard 15:17, 21 March 2007 (CET)
A method from Agenda VR3
The Agenda VR3 was a linux-based PDA, also with no keyboard. Their solution was to provide an onscreen keyboard, but in addition to the A/a/1 buttons to have a button that opened up a pad for handwriting recognition. Early versions used something called 'scribble' but later versions used XMerlin. So that might be an interesting idea.
What about to use fonts for the Input metod? is it hard? I think that the widget-keyboard could be dynamic. Connect the input with the orphographic vocabulary, so 5 most probable letters will have bigger area( enough for the finger) (fonts are scalable sometimes) As a transparent widget was shown,the bigger-letters can be on the background of the whole keyboard - each letter on its place. And you can find a little place for the button with the most probable word (may be form with variants).