$1 million 'Yo' app has serious security flaws, users say

Yo! App

While the investing world was still trying to figure out how an app that does nothing more than text the word "yo" to the recipient of your choice could be worth $1 million, news site Quartz discovered that the app has major security flaws.

The app—now the fifth most popular app in Apple's U.S. app store—can easily be hacked, Quartz has discovered.

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The app apparently reveals all user's phone numbers to anyone who requests them. Another user was able to break into the system to deliver the message #YoBeenHacked (now already a trending hashtag on Twitter).

The app's founder, Or Arbel, confirmed to TechCrunch that some flaws had been fixed without specifying which ones.