(NBC) — Spyware has been detected in multiple Android apps, NBC News reports.

According to Consumerist, spyware was detected in more than 500 Android apps, which have been downloaded a combined 100 million times.

According to mobile security firm Lookout, the apps were using a software development kit that had a vulnerability which allowed hackers to change what the app does after it's installed.

Google has since removed the apps from the Google Play Store or they were replaced with versions that had the bad code removed.

Experts say you should make sure you update all of your apps to the latest version, and they suggest using a third-party security suite or anti-malware program that can help protect your phone just like they protect your computer.