I Am Not Where You Think I Am

There is one other interesting aspect of computers (and phones) trying to figure out the current location. 

Last week I discussed what happens when an iPhone does not have the location information. This happens most likely when the phone is not connected to any network (an airplane mode) and has not managed to get a GPS fix. Then in some scenarios like tagging photos it seems to be using the last known location, which can be way off, e.g., when you're flying.

The other situation occurs when the phone is connected to a mobile network which is not local. Or maybe to be more precise - to a mobile Access Point Name (APN), which routes data packets in a private tunnel which is then connected to the public internet in a completely different place. This typically happens when you use your carrier's default APN while roaming abroad. Things can be off by 1 hour (as it happened to me in China when the phone was thinking it was in Japan) or more.

Interestingly applications and subsystems like Google get totally confused. When I bought eSIM data, which turned out to be provided by 1Global, which routed the traffic through servers in the United Kingdom, the phone suddenly switch to default to a British context. It started offering me statistics from olympic games related to British athletes. Even though I never configured any British language nor locale. A tiny detail but could be quite confusing. It probably comes down to the Google services using wrong API and also trying to be too smart by automatically detecting the context which was not the right context. They do this also when presenting a login screen to your Google account. For example if you are in Korea, the login page will be in Korean, even though the phone locale is US-English.

There can also be an opposite effect - the Garmin watch on an intercontinental flight always shows the precise time for the location I'm currently flying over (it gets this from the GPS satellites). Which is completely useless, because this is neither the departure time zone nor the arrival time zone. So the "local" time does not really matter much (or at least most people would not care). But technically speaking it is precise.