Unwanted pop-ups can be an annoying side effect of using a web browser on a smartphone. — dpa
Aggressive advertising pop-ups that block the entire smartphone display are a nuisance. If one appears, you should never tap on it – and you should certainly not enter any personal data in the input fields.
Address collectors can be lurking behind pop-ups that promise fictitious winnings. Or they may be seeking to lure you into unwanted subscriptions that will show up later your mobile phone bill.
To prevent these unwanted intruders from showing up on your screen, you should activate a third-party lock with your service provider.
Alternatively, you can prevent most pop-ups by clearing your browser cache. On Android phones, you'll find this option under settings. You should also delete cookies, while at the same time making sure that no third-party cookies are accepted and all cookies are deleted once the browser is closed.
If the ads still appear, you might have to delete all browser data, returning the phone to more or less the factory state. If even that doesn't work, an app might be responsible for the pop-ups. In that case, you should uninstall recently installed apps until the problem is solved. — dpa