Is this a phishing or hacking attempt using a survey? How do I get rid of this popup? For the last few days I have been getting a really annoying popup. Every half an hour or so my web browser randomly opens up when I unlock my phone (Samsung Galaxy S5, running Android 6.0.1) and opens up this site:

www.surveygizmo.com/s3/3191047/mul-widget-uninstall-survey




The thing is, I don't even know which app or widget they are talking about. I did not recently uninstall anything on my phone, and I don't know what the "mul widget" from the URL is. So I figured it might just be a phishing or hacking attempt by a dubious website or ad, and I just closed the tab. Then, annoyingly, the same site popped up again after a while, so I clicked on "other", added a random reason. Which did not help either. Obviously I did not submit my e-mail, but nothing helped so far and it's starting to piss me off. I couldn't find anyone who had the same issue on the internet, and the only other thing I could think of is adding a random e-mail address but I keep thinking that it looks like there is some software on my phone that has been installed by somebody else, which activates this popup.

I must stress that this popup turns up even if the browser is closed, and it opens the browser by itself.

I also ran Malwarebytes and the AVG AntiVirus multiple times, to no avail.

Does anyone know what I could do?
Try to open the list of installed apps and then inspect the list. Uninstall anything that you think you hadn't installed 
especially something like mul widget .