When the app Yo was first released, it might have beat out Facebook Slingshot on the App Store, but most believed it was a joke.

When the app Yo was first released, it might have beat out Facebook Slingshot on the App Store, but most believed it was a joke. But now some are beginning to say it has some staying power, and even that “an app like Yo could…be bigger than Twitter.” The most recent update to Yo matures the app's functions, and expands its choices so that multiple alerts/greetings can be sent at the touch of the screen, messages can be embedded with links, and hashtags can be created—all of which make the app more appealing to marketers. (WSJ, TechCrunch)