Hey! I would recommend you about an application named "Video Stamper: Add Logo, Timestamp & Text on Video" from Google Play Store.
The application allows you to customize only your saved videos. It has some amazing features like
1 ) Date and Time Stamp - where you can add both current and Manual date and time
2) GPS Stamp- to add the location of your trip and much more interesting feature.
Here is the link:- https://play.google.com/store/apps/details?id=com.autostamper.addtimestampandtextongalleryvideos
Hope, it works for you!