Simple Gallery Pro is a Google Photos alternative that focuses on being an excellent offline media viewer. For a limited time, the app is available for free on the Google Play Store. The app is open-source and available for free on F-Droid even after the Play Store promotion expires.
All prevalent image and video formats are supported by the Simple Gallery Pro app. It has a photo editor, a recycle bin for recovering accidentally deleted media, and an app lock. There are also numerous customization options available to change the appearance of the app.