Yo (app)

Yo was a minimalist social networking mobile app for iOS and Android created by Or Arbel and developed by Life Before Us. The app's sole function was to send a single-word notification—"Yo"—to other users.

The app gained significant media attention and a surge in downloads following its launch in April 2014, fueled by its simplicity and the novelty of its concept. Its virality sparked debate about the value of minimalist communication and the nature of social interaction in the digital age.

Users could add friends via their usernames and then simply tap a user's name to send a "Yo." Receiving a "Yo" triggered a push notification on the recipient's device. There was initially no text or media beyond the "Yo" notification itself.

Despite its initial popularity, the app faced criticism for its lack of functionality and perceived triviality. Later versions of the app added features such as the ability to attach location data to "Yo" messages, offering users the chance to notify contacts of their current whereabouts. Subsequent updates allowed for linking websites and sending more diverse notifications.

The app's long-term sustainability was questioned, and while it demonstrated the potential for simple, notification-based communication, its use eventually declined. While no longer widely used, Yo remains a notable example of a viral mobile application that explored the boundaries of minimalist communication in the early mobile app landscape.