ANT KATZ

Yo, which lets users send and receive messages that contain only the word “yo,” says it has funding commitments of $1 million from investors.

The San Francisco-based Yo is not another dumb start-up idea from a Stanford grad. The app was made in Tel Aviv and became a viral sensation in Israel before anywhere else.

BLOOMBERG titled their story “Don’t Blame Silicon Valley for the Stupid Yo App. Blame Israel” last week after an app called Yo became the “poster child for a technology bubble that could cover the entire Silicon Valley in chewing gum.”

The global ascent of Yo, created by Or Arbel, has only happened in the last week or so since Or moved to San Francisco. But it was already the #1 iPhone app in Israel.

And it’s rising fast elsewhere, says research firm App Annie. It’s in the top 10 in more than a dozen countries. The app has over a half-million users, and it’s growing by about 200,000 a day, according to Moshe Hogeg, an Israeli who has agreed to invest in Yo.

Aggressively simplistic, Yo lets you tap a friend’s name and send them a notification that says “Yo!” in a tiny robotic voice.

The app’s creator, Or Arbel, let out the secret last week that the tiny voice responsible for the “Yo!” notification is actually his own.

Yo took only eight hours to develop, and the story behind the app’s creation is fascinating. Originally, Mobli founder Moshe Hogeg reached out to Arbel, asking for a simple one-button notification to reach his personal assistant.

What a stupid idea, he first thought

At first, says Arbel, he wasn’t impressed. “It’s a stupid idea,” he told Hogeg. “How many people have a personal assistant that they need to send a push notification to?”

But Arbel quickly realised that he already did something similar when he talked to one of his friends, who lived in LA at the time. The two friends would text each other a simple “yo,” which is all that needed to be said most of the time.

Why “Yo”? Why not “Sup” or “Hey”?

“‘Yo’ is more than ‘hey,'” Arbel said. “‘Yo’ can mean anything. ‘Hey’ means ‘hey,’ but ‘yo’ can mean everything. It’s the perfect word. There’s no other word can be used at much.”

Last week Yo passed 60,000 downloads, and Arbel has plans to turn Yo into a non-invasive push-notification system for people to subscribe to content they like. For example, current Yo users can send a Yo to “WorldCup” and receive a Yo whenever a goal is scored.

“There’s nothing to open, there’s nothing to distract you,” Arbel said, adding that people don’t like the spammy subscription notifications that currently exist.

Arbel’s belief in keeping things simple, hence the app’s icon, a simple purple square.

Built it in 8 hours

Arbel built the app, and its plain purple icon, in 8 hours, Hogeg says. Apple initially refused to host Yo in the App Store because the company assumed it was unfinished.

Now, Arbel is looking for future development opportunities for Yo.

The Mobli crew shared Yo with friends, and it quickly took off. Hogeg says he sends a “yo” to his wife around 8pm when he leaves the office, and she sends him a “yo” from the kitchen when dinner is ready. His friends’ kids use the app to alert their parents when they’re ready to be picked up from school. Anyone can add WORLDCUP to their friends list to receive a nudge each time a goal is scored.

“A lot of the time, you don’t need anything more than ‘yo’ to explain what you want or need,” Hogeg says. “My wife complained all the time that I’m not calling her enough during the day. I tell her that every time I send you this thing, I’m thinking about you. My wife is very happy right now because I ‘yo’ her ten times a day.”

$1-million financing raised

Part of Yo’s fundraising prowess can be attributed to Hogeg, says Roi Carthy, a managing partner at venture firm Initial Capital in Israel. The Mobli CEO has a reputation for effectively drumming up excitement from investors — including for his own start-up, which counts Mexican billionaire Carlos Slim and Leonardo DiCaprio among its backers.