I can, and do use the screen keyboards on an Apple IPAD,
and an Amazon Fire HD7 Android tablet just fine.
But they are bigger. And I don't like 'stabbing at ants'
with a stylus pen on a phone either.
Just picture Fred Flintstone trying to use the teeny-weeny
keyboard on the screen of a cell phone - that's me.
Yes/No/I'll call you/Thank you/See you soon, and some other things that I have never used. It is all I need.