Thanks — I don't have a piece of hardware that can use iOS8, but hopefully I'll get my hands on one eventually.
Thanks for the suggestion LittleStain, but that demo also runs kinda slowly on my phone. It also doesn't have the ability to change colors, so I couldn't use it without WebGL anyway. And I know about the alternative to textboxes, but they're all rather clunky. If the next OS update doesn't have a big impact on how it performs, I'll try it out and see what I can do