I've read through some of the growth stories for communities like StackOverflow and Quora. It seems like the common theme there is starting with a small group of influencers and then grow outward from there, leveraging reach and content.
I am working on a mobile Q&A app I want to keep invite-only, requiring each user to be either invited by a friend or have to apply on our website. This is part of our positioning as we want to make the app more personal and helpful than something like Quora. I've still working through ideas but was curious if any of you have experience building an invite-only model.
Excited to hear your thoughts!