When it comes to cybercrime, not even your favorite app store is safe.

The International Business Times reports that fake mobile applications carried by the most popular app stores often pose phishing and malware threats. Hackers create the apps to control parts of users’ mobile phones, flood devices with spam ads and steal personal information.

They’re not always easy to spot. The more sophisticated counterfeits are designed to resemble legitimate games, e-commerce portals and social media apps. A fake version of WhatsApp, named “Update WhatsApp Messenger” had more than one million downloads before it was flagged and removed from one provider’s app store.

For information how to recognize fake apps and tips for users who have already made the mistake of downloading one, click here to read the full story.