(#iefub6q) @prologic Hmm, have you used a GPS device 15, 20 years ago? I had one in my car. It would take a long time until it got a first “fix” of your location. That’s because it can take up to 12 minutes until you have gathered all the data directly from the satellites. These days, GPS trackers on smartphones get a fix within seconds, maybe 30 seconds tops, because they get pre-seeded with (approximated) satellite positions via A-GPS. We also not only have the USA’s GPS these days but also other satellite systems like the EU’s Galileo or Russia’s Glonass. A-GPS helps you get “in contact” quickly with *more* satellites, which enhances the precision quite a lot. So, yeah, you *can* use it without A-GPS. But it would be very annoying and imprecise. I bought a new phone last year and A-GPS was broken on that one (I saw no internet traffic at all), which made it basically useless, to the point where I wouldn’t want to use it at all. I sent it back and bought another model. To my knowledge, the only way to use GPS without something like A-GPS is to have it turned on all the time, so you get regular updates directly from the satellites.

(#iefub6q) @movq Surely it isn't as bad as this though right? 🤔 I mean reading the Wikipedia page on A-GPS, it sounds to me like it sends enough data to the nearest tower to give you enough data to warm-up the GPS receivership, presumably with GPS coordinates of the tower itself? I can imagine this data payload would include the Date/Time, IEMI and possibly your SIM details and Phone number (_why not_). It could be worse 🤣

(#iefub6q) I can't imagine it's a static URL either, it surely has to be a unicast address of some sort. Relying on a static URL sounds like an utter disaster to me 🤔 I'd have to read the open spec on this...

(#iefub6q) Okay, GPS performance has degraded a lot over the last few days. - Time to first fix is a couple of minutes now, instead of 5-30 seconds. - Accuracy is reduced greatly, probably because the phone can one lock on to about 6-12 satellites, this used to be around 30 satellites. In theory and under good conditions, you need 4 satellites to get a fix. But in reality, there are rarely “good conditions”, there are always buildings, hills, or trees nearby, so you need as many satellites as you can possibly get. It’s not *completely useless* (yet), but it’s not great. I think I’m gonna lift some firewall restrictions. 🫤

(#iefub6q) The GPS satellites transmit an almanac, a (coarse) list of all satellite positions: That’s apparently crucial for a low “time to first fix” and, as I understand it, that’s where A-GPS comes into play: Downloading this information from the satellites takes about 12.5 minutes, but downloading it via the internet (A-GPS) is much faster. So the question is: How long is this data valid for? It’s a bit hard to find information on this … It looks like it’s valid for several *weeks*: If true, it would mean the situation is much less dramatic than I thought. 😅 I go on a walk every couple of days and that gives the device more than enough time to download an updated almanac. So, I *guess* I should be fine without A-GPS *if* I regularly use (standard) GPS for an hour or so. 🤔 We’ll see. This might take a couple of months to find out. 😂

(#iefub6q) @movq Well I used to have a handheld GPS device, probably before I lost most of my sight. I didn't really feel that it took ~12m to get a fix, it was usually much faster. You _may_ just find that all this A-GPS thing is all just bullshit anyway and just an excuse to collect and store your GPS location on some random web server that someone else owns 🤣

(#iefub6q) I’ll make an experiment: I’ll keep blocking all the phone’s internet traffic and then we’ll see how bad the GPS performance will get in a couple of hours/days. 😅 (If I got it all wrong and it still works fine, that’d be great!)

(#iefub6q) @prologic Regarding the static URL: The hostname at least is a CNAME record and resolves to something at cloudfront. What I meant was that I, as a user, cannot configure this URL anywhere in the Android UI. 🤔

(#iefub6q) @movq Look forward to the results 🤞

(#iefub6q) @prologic I sure hope you’re right. 😅 I’d love nothing more than not having to rely on the internet for this. 🤞 (I clearly remember sitting in my car and waiting an eternity to get a fix, though. I’d regularly start the GPS device and then continue to load up my bags/stuff into the car because it took so long. 😅 Maybe it was just a shitty device, who knows …)