No, because I think it would probably be bad.
Think about that, touch-screen keyboard combined with literally the smallest screen you can get that sounds like the worst coding experience. Not to say the fact that, if you hold the screen vertically, you may not see all of the characters in one line; if you hold the screen horizontally, your touch-screen keyboard will occupy most screen spaces. Come on, everyone used SSH on your phone sometimes and know how it feels.
I'll tolerate reading source code on my phone, but coding.. at least on an iPad.