(Radio Iowa) – Iowans are warned to be careful when scanning Q-R codes with their phones. Those squares with the jumbled black-and-white dots and lines that resemble a game of Tetris can be helpful in getting to menus, websites and coupons, but they can also mean trouble. Consumer protection expert Michael Domke says always check where that link is going before you click “okay” on your phone.

Domke says, “It’s important to make sure when you are scanning those codes that it’s taking you to the location that you wanted to go to, or appears to at least.” Scanning malicious codes could open up your phone to malware, hackers or other problems. If you end up with malware on your phone, Domke says you could have to factory reset your device, in the worst case.

“The loss that you’re going to suffer through maybe one of those previous state restarts is going to be far less than letting the malware run rampant and having somebody steal all your information,” he says. If you’re unsure about a code, use your phone’s Q-R software to scan it or use an anti-malware program. Domke says to treat Q-R codes like any link you might get in an email — if you don’t trust it, don’t scan it.