evalda you have to be outdoors (open sky)
This is not true. People also say here that GPS location does not work indoors which is provably incorrect in my experience.
I reliably receive 21-25 GNSS satellites inside and obtain a location fix (lock) in the ground floor of a multi-storey building and also inside commercial buildings with steel roofs, and on a city bus or train.
Ability to receive GPS satellite varies. Factors include the users lattitude, the sensitivity of user's phone's satellite receiver (varies by model and between individual units) and the orientation and exposure of the phone. e.g. closeness to a car windshield or in a pants pocket blocked by the body.
A user can test see GNSS satellite reception details with the app "gpstest" and also use that to optimize placing the phone into an optimum location for receiving GNSS broadcasts.
Additionally, while on the road, the number of local wifi access points and bluetooth beacons diminishes and there may be none at all to provide navigation help, and they will be passed quickly so they are of diminishing to zero value.