There's nothing on their front page about how it works. I tried applying for an invite out of a leap of faith, but I don't qualify as I don't have an account with any of the below. I wonder what sort of customer they're trying to filter for.

To get an invite:

    Send a private message to @ebookfarm on Mobilism [Must have an active Mobilism account]

    Send a private message to @ebookfarm on Reddit [Must have an active Reddit account]

    Send a private message to Ebooka Farmer on Facebook [Must have an active Facebook account]