Can I use actual physical location of phone? (and not mast miles away?)

First posting!
Before starting to use this system, I would like to know can it create an app that will
hide / show items on a map based on the actual physical location of the phone (i.e the geolocation)

Most similar systems only seem to show the location of the nearest signal mast (which could be several miles away)

I would like to create a map that displays info about where the person is stood but it needs to be accurate to several meters.