@prologic@twtxt.net 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.