I built the first Android Twitter client, sold that to Idealab* and given our huge market share (~40% IIRC ) pitched them the idea to build our own Twitter clone in order to move those users over. Twitter took notice and locked all our apps which eventually kicked off the anti-third-party tendency that we see today. Good times.
* https://bgr.com/general/tweetup-acquires-twidroid-renaming-a...