The world's live Q&A app
vectrapp.com
vectrapp.com
One thing I find annoying right off the bat is that this is an app only: there's no web version.
If you did want to actually spend your time answering questions, you'd be forced to do it on your phone instead of something with a full keyboard, screen real-estate and multi-tasking.
I'm not sure how they find experts (seems like they'd just be normal users who happen to get high ratings), but I wonder how they plan to prevent burn-out?
I know I am not alone in hating answering the same questions over and over. I actually make a very conscious effort at work to answer questions people ask me by updating our documentation (tickets, wiki pages or source) whenever I possibly can, even if they send a 1-1 chat message. It takes more time than answering directly, but it takes less time than providing that same answer a second time.
In fact, you see on communities like StackOverflow that some people seem to almost delight in closing questions after they've hunted down the duplicate.
So that seems to me to be a big barrier to sustainability. Enough user volume and churn is probably the only way to combat this -- keep bringing in fresh people willing to answer the same questions -- but that can only go so far.