If you’re not familiar with the process, you can sideload apps on your smartphone to get around official app store restrictions. While this can be a fun way to try out custom apps, it can also be dangerous.
Take, for example, FMWhatsApp; this program is a “modded” version of WhatsApp. That means that it lets you chat will all of your WhatsApp friends, but gives you access to features and customizations that the real WhatsApp app doesn’t. At first, it sounds like a blast.
Unfortunately, it’s a mess. The app was found to be carrying the Triada mobile Trojan; this malicious code is silently installed on devices using FMWhatsApp, and proceeds to open ads, read SMSs, and launch subscriptions.
It’s a good reminder to always download your apps through proper channels, like Android’s Play Store or iOS’ App Store. If you’re going to sideload an app, make sure it’s from a vetting organization, like APKMirror.