Lookout, a smartphone security app, said its software will now flag adware -- mobile advertising that could be a security risk -- on Android devices.
The company defines adware as mobile advertising that interrupts users' experience. Some malicious adware has been known to surreptitiously gather the user's contact information.
Lookout updated its Android app Wednesday to quickly notify users know if they have downloaded an app that contains adware.
If Lookout detects adware has been installed on a user's phone, it will let users choose to either ignore the threat or begin a removal process that will uninstall the app containing intrusive mobile ads.
The company said adware is prevalent in 6.5% of the apps found on the Google Play app store. It estimated that adware affected more than 1 million U.S. Android users last year.
Adware can come in a number of different forms. Sometimes, apps containing adware will display ads in unusual spots, such as a phone's notification bar or home screen.
Some particularly damaging adware performs unexpected actions when users click on ads, such as sending out text messages from the device or making calls on their own.
Jeremy Linden, the security product manager of Lookout, said adware is usually not found on respected apps. Instead, the adware will more commonly show up on apps developed by smaller companies.
"It's generally applications that are smaller houses that may not understand or care about the impact that adware would have on their user experience," Linden said.