I received many more messages than usual on my iPhone during the past 24 hours. "Trying this out!!" from a colleague. "Howdy!" from a girlfriend. "Are you coming home soon?" from my husband. "Yep, I'm already bored with the story, but I'm definitely paying attention," from a former colleague who's now a tech reporter.

Pretty normal stuff. But none of those words actually appeared on my phone screen. Just one did. What popped up on the screen--over and over--was "Yo."

For the past day or so, the breakout app--at least for websites that report on tech and culture, and all the people having a lot of fun with it on Twitter--has been one called Yo. It's the simplest communication app to date, and its minimalistic user interface (just a jewel-toned, blocky, scrollable list of your contacts who also use the app) is matched in barebonedness by its functionality. Touch your contact's name, and it sends them a push-notification text and audio "yo."


Neither my college communications courses nor my persistent fascination with both language and linguistics prepared me for this phenomenon of wordless virtual communication. 

"Why am I using this?" "This is idiocy." "Can you send me another 'Yo?'" "This is addictive." These are other things my "yo"s may have meant. And this is precisely the point.

The app has been lauded as a spoof, dismissed as utterly pointless, and highlighted as a sign of the looming tech-bubble-apocalypse. It's also been hailed for its ingenuity.

I, for one, briefly hoped it was performance art.

The buzz started when news the company behind the app--which bills itself as "zero characters communication"--raised $1 million in angel investment. According to TechCrunch, four million Yos have been sent since the app launched in April. Today, the company tweeted that it has 200,000 users. Not bad for an app that reportedly took Israeli entrepreneur Or Arbel all of eight hours to code.

Fact is, you know your friends well. You pretty much know what they're going to say--or at least what they mean when they reach out. Sometimes the words don't matter so much. As Jordan Crook writes in a (seriously) 1,600-word think-piece on the app that barely does anything:

As with anything, a "Yo" can just be a yo. But you’ll feel a very real difference between a "Yo" you get in the morning from a friend and a "Yo" you get at 2 a.m. from a friend with benefits. Trust me. And that’s… supposedly… the magic.

Perhaps with communications apps, context, not content, is king. If nothing else, Yo certainly feels like it is taking the ephemerality trend to its logical, albeit absurd, and most stripped-down, conclusion.

Venture capitalist Marc Andreessen is bullish, and Business Insider pulled together his tweeted thoughts, explaining:

"[T]here's a fascinating aspect lots of people are missing," tweeted Andreessen on Thursday morning. "Yo is an instance of "one-bit communication"--a message with no content other than the fact that it exists," he explained. "Yes or no. Yo or no yo. Other instances of one-bit communication: Police siren, flashing stop light, "Open" sign, light turned on, taxicab roof indicator lit."

And he points to the instance of the "missed call phenomenon" around the globe, explained fairly succinctly here in Wikipedia:

A missed call is a telephone call that is deliberately terminated by the caller before being answered by its intended recipient, appearing as a "missed call" on the receiver's cellphone. It is commonly used in South Asia, the Philippines and Africa as a way of communicating pre-agreed messages for free. For example, a group of friends may agree that two missed calls in succession means "I am running late". In Bangladesh, missed calls make up 70% of cellular network traffic at any given time.

Only problem: Yo doesn't mean anything aside from "who" and "when," yet. Maybe it will. Maybe the app will stack on features over time (on Thursday it allowed users to receive a "yo" every time a goal was scored in a World Cup match). Maybe it will figure out a way to monetize one-bit communication, or go the way of other messanging services it's borderline mocking (Viper sold to Rakuten for $1 billion, and Facebook shelled out $19 billion for WhatsApp)  and someday pay back its investors.

Or maybe it will always be our favorite app of that one week in June of 2014, that Year of Ephemerality. The Yos will all be vanished, but at least the Tweets will stick.