It's possible that you have some inappropriate images on your phone, and it's also possible you will occasionally receive more of them. I'm not here to judge, but there's a new app that judges for you what is and is not NSFW. Cover automatically finds and segregates NSFW photos and videos on your device, even if you've forgotten they're saved. It can operate in the background to hide such items before they appear unexpectedly in other apps, too.

Cover uses a machine learning algorithm to scan content for nudity, which is similar to the systems in use on sites like Facebook. It works offline, so it can take some time to go through all the files on your phone when you first install. Although, you can skip this and just scan new items as they appear. In real-time mode, Cover watches for new files and scans them within seconds.

In apps displaying NSFW files, Cover swaps in a blurred placeholder. The original files aren't gone—they end up in the Cover gallery where you can lock them away with a password or fingerprint. I have valiantly tested this app and can confirm it is able to detect NSFW content with no false positives. You're welcome.