Location registration takes place when a mobile station is turned on.This is also known as IMSI Attach because as soon as the mobile station is switched on it informs the Visitor Location Register (VLR) that it is now back in service and is able to receive calls.This information, and more, is available in the , as illustrated in the lesson on Getting the Last Known Location, a more direct approach is to request periodic updates from the fused location provider.In response, the API updates your app periodically with the best available location, based on the currently-available location providers such as Wi Fi and GPS (Global Positioning System).The TMSI is used for security purposes, so that the IMSI of a subscriber does not have to be transmitted over the air interface.The TMSI is a temporary identity, which regularly gets changed.
For this purpose the MS periodically reports its location to the network using the Location Update procedure. If the mobile moves from a cell in one location area to a cell in another location area, the mobile phone should perform a location area update to inform the network about the exact location of the mobile phone.
"This map isn't about where am I, it's about where are my friends and what are they up to?
It's not about figuring out how to get to your destination, but about discovering where you want to go."When you open the updated app, you'll be walked through a series of onboarding steps which will show you how to get to Snap Map: From the main camera screen, simply pinch your fingers together, then the app will ask you to choose from among three visibility options.
You can get a very good detailed message flow of Location update in Hope this helps.
Tip: To quickly turn on your location, swipe down with two fingers from the top of your device’s screen tap Location.