Enabling GPS lets you use location services on Samsung Galaxy S4. You also need to allow some apps and Google to use your current location. To turn on or off location services on Android Galaxy S4 do as follows:
1. Open "Settings" app
2. tap on "More" tab
3. tap "Location Services"
4. Enable "Access my location"
5. You need to agree with Location consent in order to use this feature
6. You have 2 options:
a. use GPS satellites: Allows apps to use GPS to pinpoint your location
b. use Wireless networks: Location determined by Wi-Fi and/or mobile networks
** You can always enable or disable GPS from the notification panel
See: Best Android GPS App
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