A free program for Android, by Whizpool.

This application allows you to hide your photos, videos, and other files in a secure place. You can even secure the private content with a PIN, touch, or face ID. If someone tries to open the folder with the wrong password, they will only see a dummy folder and your private data will remain hidden.

If you want to add any photos, videos, or other files to the secure place, you can do that with this application. Just import the file you want to secure and create a folder. You can even nest those folders to further organize your content.