Upgraded Location Privacy
iOS 13 now includes a new privacy controls for your location and security. This includes enhanced app location information and preventing apps from using other factors to figure out where you are.
When you open an app in iOS 13 it will ask you about location usage like in iOS 12, but now you can say to only allow your location once, and see the prompt the next time. When an app is using your location in the background you'll also get a notification to see if you want to keep allowing this.
Some apps can use WiFi and Bluetooth information to figure out where you are. Now you need to manually allow this for the apps to figure out where you are.
When you share photos on social media you can now choose if you want your location to share as well.