The free app, which is simply called "Yo," is available for iPhone and Android users. Developed by San Francisco-based Life Before Us, LLC, the app's creators describe it as "the simplest & most efficient communication tool in the world."
Yo is a single-tap zero character communication tool. Yo is everything and anything, it all depends on you the recipient and the time of the Yo. Wanna say "Good morning?" just Yo. Wanna say "Are you up?" just Yo, according to the app store description.
Download Yo app and choose the friends you want to send your "Yo" message to and they get a push notification on their phone and that's it.
