GPS when roaming with no data What kind of GPS functionality should I expect on a roaming Android device that has mobile data disabled when I am abroad?

I have just found myself a bit stuck with Google Offline Maps because my rooted Galaxy Note 3 running Resurrection Remix would only get a correct GPS fix once mobile data roaming was turned on - before turning on mobile data, the phone thought it was at its previous good location. Once mobile data was turned on, the phone got a new GPS fix very quickly despite being in a heavily built-up area. Turning off mobile data would cause the GPS fix to be stuck at this new location.

As an example:


come out of a Metro Station A, fix from previous good location
turn on data, fix very quickly
turn off data, fix sticks at location of Metro Station A
go into Metro Station A, and travel to Metro Station B
come out of Metro Station B, fix still shows location of Metro Station A


I have tried changing the settings on the GPS to tell it to only use the GPS satellites (and not wifi/cellular) but this didn't help.

Is this expected behaviour, a quirk of the Note 3 or Resurrection Remix, or something else?
All current GPS chips can work in one of two modes: GPS Standalone or AGPS (either MS-Based or MS-Assisted), where AGPS is the abbreviation of Assisted-GPS. The latter requires internet connection to contact an AGPS server which helps the chip to get its first fix.

When on gps standalone mode (in your case when you deactivate mobile data), the chip is not assisted in any way, and it may take about 12.5 minutes to resolve its location.

Read more on wikipedia.