Your phone shows your location on the map using a satellite positioning system, Wi-Fi, or network (Cell ID) based positioning.
Some satellite positioning systems may require transferring small amounts of data over the mobile network. If you want to avoid data costs, for example when traveling, you can switch the mobile data connection off in your phone settings.
Wi-Fi positioning improves positioning accuracy when satellite signals are not available, especially when you are indoors or between tall buildings. If you're in a place where the use of Wi-Fi is restricted, you can switch Wi-Fi off in your phone settings.
Tap Settings > Security & location, and switch Location on.