How do I get rid of popup ads?

[quietdignity]

In the last couple of weeks, my spouse has been getting popup ads at weird random times (like when the phone wakes up for a text message, we have to get rid of an ad before we can read the text).  I have the exact same kind of phone (Casio Commando 4G LTE), although not the exact same apps, and I never get them. We did go into the Google Ads setup and opt out of the interest-based ads, but this has not stopped the problem.

Is this being caused by an app?  How can I figure out which apps have been updated or downloaded most recently (since those would be the most likely culprits)?

[Snn5 · Accepted solution]

Most likely an app.  Maybe a game app.  You can go to the Play Store desktop version and log in.  You can go to apps, my apps, and view what you have downloaded.  The most recent ones are at the top.  Also can be done from the Play Store app.

[quietdignity]

Thank you!  I'll see what I can figure out.