[Galaxy S I9000 General] herbert1:
As explained before (in some previous post), ntp servers send you their current time, but there is also an evaluation of how long it will take for the answer to reach the client, so the ntp distance is not really a problem. On a normal computer (eg a linux system), the ntp server will be used to evaluate and compensate the internal clock drift (so after some time you will have correct accuracy without asking time too often). With a closer ntp server you can expect that the network latency will be lower and more stable, so you can have better accuracy (however geographically closer don't always mean closer on the network...).

Many GPS send a fix every 1 seconds, some (at least some expensive marine or standalone ones) can send 2, 5 or ten fix per seconds, but it's not very relevant here. On the phone the ntp server are used to initialized the GPS clock and accelerate the first fix (see below). In either cases the distance (and the network latency) between the ntp server and the client is not so important.

The GPS satellites are sending atomic time to everyone: "I'm here, At this time". So GPS are sometime used as time reference for a ntp server...

How does it work ? You have all these satellites that tell you: "I'm here, At this time". The signals take some time to be received (light speed etc...), so there is a little delay between the different signals and between the real time and the satellites time, these delays are use to compute the distances between the GPS unit and the satellites, so you know were you are... If you see 4 GPS satellites you should be able to know, where you are and what time is it... The problem is when there are not enough sats (or if there are all in the same region of the sky...)

All standalone GPS have a internal clock, if this clock is not synchronized ( ntp/radio/aso) they will wait until they see enough GPS sats to have a valid fix (with position and time), then they can compute your position even when less sats are visible...

However the precision of this clock is very important: for 1µs (0.000001s) error you will have a 300m (980ft) error. So if the GPS clock (not the phone one) is not good enough you will have a bad accuracy, mainly if you don't see enough satellites...

So accurate time give you a faster fix.

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I've tried some, and yes SGS is worse than many (except perhaps iphone which use the same chips...).

If the GPS clock is bad, you will need to see more satellites to have a good fix. If antenna is not well designed it will be difficult to have good reception (you will need higher signal), especially inside buildings, cars, on cloudy weather, aso. If the environment is noisy (eg. you're fetching data using the 3G connexion), it will be even harder...

If you disable A-GPS, then it can be quite impossible !

For many smartphone manufacturers GPS is not a priority (and many users just want a gps which gives a quick fix with small accuracy), for that a cheap A-GPS (and sometime cheating a little in order to compensate insufficient design) is sufficient.

However some devices are better than other. Galaxy Note uses GPS and GLONASS (Russian version of US GPS): slightly different technologies, more satellites and consequently better accuracy (and possibly also better design...)