If you go to the location settings on your device you have the options of:
- High Accuracy
- Power Saving
- GPS Only
Where Off and GPS only are obvious, Power Saving uses Wi-Fi & Mobile networks only and High Accuracy uses both GPS and WiFi/Network information. (I am running 4.4.2 on my Galaxy Note 3).
The reasons for the multiplicity of choices are the balance between accuracy and battery life,
- GPS can give good accuracy anywhere so will work even if you are out of range for all calls or on holiday with roaming turned off,
- Network information depends on the availability of towers &/or WiFi with the geographic information set up but will be either be connecting to towers or querying WiFi both of which have some impact on battery life but not much more than being able to receive calls,
- Both uses the most power but will produce faster, more accurate, more reliable, results than any single method.
So now the user of the device has the choice and if your application relies on one specific method it should query the available information and if it is not enabled prompt the user.