This is more of a long-term feature request, particularly in the light of the current disabled status of MathJax in the app, but I'd still like to ask for it now so that it (hopefully) gets considered soon.
Using the 'technical', TeX-heavy sites on anything that doesn't have a full-blown keyboard has always been a sub-par experience. Viewing, commenting, reviewing, voting, and even some minor editing tend to work well, if you're prepared to go a long way to reach those
]s, but writing a TeX-heavy question or answer on a mobile keyboard is out of the question for any reasonable person.
However, the introduction of the Android app sets the scene for a change in that situation. There are already a few existing stylus-to-LaTeX systems on the androidsphere such as S Note on certain Samsung devices (though I'm unsure how many such systems are open enough to implement within another app).
If it becomes possible to handwrite a TeX-heavy question or answer directly within the StackExchange app, then this changes the game and it brings the technical sites into a full mobile life. More than that, this can even provide an even more natural way to write math-heavy questions and answers than the keyboard itself.
I know, on the other hand, that this is a long way off. In the meantime, what systems are there that could be built upon to do this? Would it be possible to make this available to any generic stylus on any phone or tablet? Would it be possible to incorporate specific systems like the S pen? Is there a way to break the feature down into smaller stepping-stones that are more easily achievable?