Not much for me anyway. There is no way I am going to jailbreak my iPhone just to have a Colemak layout on it. Last year that was one of the lesser reasons I was waiting to buy one (the price being a bigger isssue and the lack of 3rd party apps being the other). I had hoped that Apple would make it possible to easily rearrange the keys. After all why not? It's a virtual layout. That's one of the strengths. It's really stupid that you can't. Anyway by now, I have Colemak layout well memorized and I have learned to live with and tap pretty fast with my thumbs the Qwerty layout on the iPhone (though yes it still irritates me that I can't have my favorite layout on there when I show stuff to people who ask me about my phone).
If this was free solid app being introduced into iTunes store as a way to advertise for this site with promo material on the arguments for using it for touch typing on a normal keyboard and directions to the Colemak.com website, that would be huge!
How big is the set of those using a jail broken iPhone and using Colemak. My guess is not big enough.
It's mostly an awareness/advertising thing I guess. I don't think any layout is going to be very effective on a mobile phone. The world needs a much better way of entering writing on hand-held devices.
I have an idea, but it's still on the 'mad science' stage. We'll see...
Would be interesting to see if having a period and comma readily accessible with on the wide keyboard view helped my thumb speed and accuracy. Right now the wide keyboard setups feel a little to spread out for Qwerty but I think that with Colemak it might be just the right spacing.
but yeah, it's about raising visibility.