Edward Snowden is back in the news, talking about a plan that the NSA had to have malware in various app stores, like the Google Play Store, and Apple iTunes Store.
The NSA program was called IRRITANT HORN, with the US spy agency wanting to find the path of web traffic to and from mobile application severs that are owned by Google and Samsung. Once the NSA found this traffic, it would place an attack in the middle, where it could silently inject malware and spying tools into a mobile device of its choice.
After it had planted this software, it could pull out e-mails, texts, search history, call records, videos, photos and anything else you have on your device. Thanks to the user thinking they're on an official app store, they would be unaware that they're being attacked by the US government in the form of the NSA.