not something vague and big like: ~ "Can you improve the forum's mobile-friendliness?"
Would a btalk app be a realistic possibility.
Whoops

But who knows, I've seen posts about a possible API, which puts an app one step closer. I'd
never use my real account on a mobile advice though, so it's not for me.
Built in photo upload option.
I think this is limited by "legal", not "technical". See:
If you are complaining about an image located at ip.bitcointalk.org: That image is hosted elsewhere, and we are only proxying it from the original location in order to protect user privacy. You should not complain to us.
I don't think theymos wants to deal with copyright issues.