Jesse Pinkman would be proud. A new app called Yo has raised $1 million in funding and is creating a huge buzz online, not least because of the supremely minimal concept behind it. It's just an app that lets you say "yo" to your friends. That's it. 

We'll let its description in the app store speak for itself: "Wanna say 'good morning'? Just yo. Wanna say 'baby I'm thinking about you'? Yo. 'I've finished my meeting, come by my office.' Yo. 'Are you up?' Yo."

After you download the app, you're prompted to create a username and allow Yo to access your contacts. Once your friends join the app, you can then send them "yo" as often as you want. Simple, yo! 

It might sound like the dumbest idea ever, but 50,000 people have already sent about 4 million "yo's" since the app was made available on April Fool's Day. Its developers are deadly serious that it isn't a joke: they claim that they've received $1 million in funding. 

Yo's creator, Or Arbel, tries to explain the beauty in the one-note joke. "It's zero characters – you can't get any simpler than that," he told the Financial Times. "We have decided this is an idea with great potential."

You can download Yo from the Apple and Google Play stores. In the meantime, here's a Breaking Bad supercut of Jesse Pinkman saying "yo":