Yo app warns of missile strikes in Israel
Israeli developers send out 'Yo' messages when an incoming missile is detected

The much-maligned Yo app, which does nothing but let users send the word "Yo" to one another, has found a practical application in Israel where it is being used to warn people of imminent rocket strikes.
Followers of the RedAlertIsrael account receive a Yo whenever a missile is detected heading towards Israel.
The service is designed to be used alongside a separate app called Red Alert, which provides real-time information on mortars and rockets being fired by Palestinian militants into Israel, the BBC reports. But not all experts are convinced of the service's usefulness.
Subscribe to The Week
Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

Sign up for The Week's Free Newsletters
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
When the app users send friends a "Yo", it appears onscreen as a text alert with no other information. Since it launched in April the "unlikely hit app" has been downloaded by two million smartphone users around the world.
The creators of Red Alert – Ari Sprung and Kobi Snir – say the notifications are not intended to stand alone, but are designed to help provide information to a larger percentage of the population who may be at risk from rocket attacks.
Information for the app comes from the Israel Defense Force and the Homefront Command, Sprung told the Times of Israel.
Tech entrepreneur Dvir Reznik, told the BBC that the Yo alerts seem like an inefficient way to provide information.
"If I'm on one side of Israel and a missile lands miles away, the Yo warning is not of much use to me," he said. "However it's better than nothing and I can see this evolving into something more meaningful, but it needs more substance to make it as convenient and as useful as Red Alert".
Digital Trends' Williams Pelegrin says that even though Yo has fairly basic functionality, "there’s no denying it’s being put to rather interesting uses".
Palestininans in Gaza currently don't use any apps similar to Red Alert, The Wire says, but instead often rely on Twitter hashtags such as #airstrike for updates.

Continue reading for free
We hope you're enjoying The Week's refreshingly open-minded journalism.
Subscribed to The Week? Register your account with the same email as your subscription.