When travelling to foreign countries, ie. when a data connection is unavailable because I don't want to spend big bucks using a roaming data connection, I noticed that GPS is virtually never available.
It can take hours for GPS to show my location, and even then, only when I'm located in open areas for a long time, with no buildings or trees. The only time GPS is available is when the phone is connected to the Net through wifi, which is pretty much useless.
I am using a Galaxy Nexus running CyanogenMod, and the phone has the FasterGPS utility installed.
Can GPS be available in cities without a data connection?
Best Answer
In theory, yes.
However, you must be aware of a few things:
1) GPS does not work well on high latitude (GLONASS is better in this case)
2) When you change location, the GPS needs to get information about the position of the satellites (so called almanach) for efficient use.
3) in cities, especially with tall buildings, the satellites are "hidden" by the buildings. Therefore you may not have enough "visible" satellites (4 are necessary) to compute a position.
4) The GPS satellites are moving and you don't have the same number all the time. Usually in open areas you always have enough satellites, but as I said you need more chance in "closed" areas. There are softwares to know the best moments (based on the almanach, the location and the field of view)
5) Eventually, I don't think that Galaxy Nexus has a good GPS sensor. The price of a GPS may range from 100 to 20000 $ and this obviously leads to a large difference in terms of correction for multiple travels (signal bouncing on a building), precision (15 m to a few cm...). You use a phone for locating yourself, with a GPS add on. The phone based location (using GSM towers) is therefore far better than what you get with GPS signal.