[Touch Pro, Fuze General] maw:
I am starting to agree with your conclusions Whyfish.... Actually the GPS signals transmitted from the sattelites have a built-in inaccuracy designed by the US Defence Department who own the GPS sattelite network. GPS module producers compensate this descrepancy in the GPS chip to adjust the allignment to get a near accurate reading. I'm now wondering if they forgot to compensate this descrepancy in the GPS chip causing the it to give the raw GPS position directly from the satellite without correcting the data to be able to be used in GPS navigation software. Normally there is a descrepancy between 10 and 15 meters. If this is the case, then I think the manufacturer should make a hotfix for the GPS chip to adjust and fix this problem since everything we have tried to remedy this problem doesn't seem to fix the lag problem we are experiencing. It could be that Tomtom and iGO assume that the GPS chip is correcting the descrepancy and their software isn't made to correct it. I'm just guessing that this is the problem we are facing at the moment.

I too would like to know the answers to question 2 from the different users out there that are using Tomtom and/or iGO and have been able to get rid of the lag. What did you do to solve this? Unfortunately a lot of people that fix the problem never report back to others what they did. Lets hope they do now because 1000s of people are facing this problem and its really frustrating! If however my gut feeling is right that the problem is with the chip not correcting the GPS data being received from the sattelites, then HTC better come with a patch or update for the GPS chip a.s.a.p.!!

As far as question 3 goes, I haven't noticed any battery drain at all with this registry tweak, although I'm not getting the results that I had hoped for.....

That's my 2 cents on this matter... I will keep an eye on this thread to see what others reply....

Conclusions:

0. No one has done very careful tests. It's the blind leading the blind here. Caveat Emptor.

1. Not likely to be a CPU usage issue (per http://xdaforums.com/showthread.php?t=420460). I don't expect (but I am not 100% certain) that fetching the data from an external GPS versus fetching it from the internal chip should make a difference to the CPU usage.

2. Some of the registry fixes are an improvement, but not a complete fix. There is still a significant lag of roughly .5 - .75 seconds.

3. Using an external bluetooth GPS is much better, so I think it's a hardware or communication buffer issue.

4. Tests with googlemaps are difficult, because I have registration (i.e. alignment) problems. Sometimes, it seems that the maps are offset and sometimes not. I wouldn't recommend using googlemaps for tesing.​

Things I'd like to know:

1. Can this be reproduced on other stock Sprint TPs ?

2. Some people report that things are completely fixed.

Are you really getting no lag at all?

It is the tip of the arrow in Tomtom or the middle of the arrow that is aligned with where you are?

Does your real position and GPS-indicated position match at all speeds?

3. Does the \Drivers\GpsOneDevice\PollInterval -> 100 (default is 1000) change change the batter drain?​

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