Have you taked photos with your camera and the localization function (GPS) switched on, then will are stored this location data in the photos-metadata. This app shows your photos on Google Maps based on this data.
The photos can be displayed and enlarged in the integrated Photo Viewer. It shows you the file name, title, recording time, marks and facial recognition (at time only Panasonic).
If no GPS data exist, these photos are displayed in a list. From this list, you can drag the images directly on the map and thus set the GPS data retrospectively. The deleting of GPS data is in the integrated Photo Viewer possible.