An excellent narrative of how Twitter's new Video component was developed for iOS, by @Stammy and worth a read. Beyond the technical challenges, it prompts designers to think in terms of interaction and animation.
In mid-2011, Twitter rolled out the ability to natively tweet photos. 2013 brought media-forward timelines with inline photos. 2014 ushered in multi-photo tweets and animated GIF support. We've just announced Twitter Video to help you capture the moment and tweet video from within the iOS and Android apps.
You can find the full article by clicking here.