Whenever a digital photo is taken, besides the actual image a lot of other information is also collected. Typically this will be the date and time the photograph was taken, the make and model of the camera and the exposure setting used. Depending on the camera other information will also be stored.
Cameras within smart mobile phones will also usually record the actual geographical position of where the photograph was taken. They do this using their built-in GPS. Unfortunately very few normal digital cameras have GPS capabilities. Thus getting geographical location information is a problem for most photos taken with digital camerals.
Many specialist GPS units have the ability to geotag. Geotagging is basically recording the actual path taken by the GPS unit.
There are now apps available that, once loaded and running, convert a smart mobile phone into a geotagging machine. One such app is Geotag Photos Pro. Besides actually geotagging, this app produces a resultant file that can be directly loaded into the Adobe Lightroom system that the GPR uses to modify grave photo metatags.
Once you have the app on your Android or iPhone, the most important thing for you to do is to synchronize the date and time on both the mobile and the camera. If these are not synchronized then the photos you take will not match the geotagging information on you mobile.
Once you are at a cemetery and ready to start photographing grave monuments, you must start the Geotag Photos Pro app. You can then go around a cemetery and your route will be geotagged. When you finish your photography session, turn off the app. You will now have a file containing the geotracking of you photographing trip around the cemetery. This file needs to be included with the photos you send to GPR.
The GPR will process the file so that geo referencing information is added to each photo. This means that the exact location of the grave will be available to everyone wanting a copy of the photo.