If you do have Location Services enabled on your iPhone, apps (and system services) that you approve can check your location. Here’s how you can switch GPS and other location-tracking methods off and off, quickly.
Open Settings now.
Scroll down and choose Privacy.
Press Location Service.
Scroll down to System Services. It’s supposed to be at the bottom. Press it down.
Scroll to the bottom to the Significant Locations and press to confirm. You’ll need to enter your password or activate your Face ID or Touch ID.
You can totally deactivate this feature by untoggling the Significant Locations at the top.
Alternatively, you can delete the most problematic entries individually by pressing them separately.
Press the Edit button in the upper right corner, and you can delete each entry individually.
Phone applications will no longer be able to track your location. If you want to fine-tune which apps can or cannot access your location without completely turning off Location Services, you will need to visit and configure each app entry on the Location Services page.