I built a site similar to ask.fm. It's fully working but could be extended a lot with more features. It's a web app at the moment, but could be also easily ported to a Android/iOS app. I am looking for someone who has the skills to market this app so it gets users.
The good thing about it is that there's no chicken-and-egg-problem, as people usually only see the link from someone's instagram and ask them a question.
I would be happy to split revenue 50-50, I do *all* the tech stuff and you do *all* the marketing.
Please contact me if you're interested and I'll send the site and more details.