Time stamp inaccuracies between Mytracks and bulk GPS logger

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What steps will reproduce the problem?
1. use MyTracks and bulk GPS logger (or Garmin GPS device) simultaneously log a 
track
2. export to GPX and load tracks in GPS Action Replay (sailing analysis), 
GPSAR333bis is "free version". Use timestamp-mode in GPSAR
3. press track play at GPSAR and see how MyTracks and GPS logger has timestamp 
difference.

What is the expected output? What do you see instead?
When logging a track I'd expect trackpoints to use GPS-based (better stratum 
than Android OS) timestamps on trackpoints. Instead it seems that logging uses 
Android-system timestamp which could be off many seconds. Android system 
timestamps usually comes from operator network updates. And operator usually 
gets time from..... GPS. But lag and not efficient system causes network time 
to be inaccurate.

Expected output is that MyTracks & GPS logger trackpoints should be with-in 
accuracy at same point at same time. For example yesterday I did a test and 
Galaxy S3 clock was 3 seconds ahead so on GPS Action Replay the Galaxy was 
"ahead of time" compared to GPS logger which operates on GPS clock. As on GPS 
logger you don't set any clock, it just stores trackpoint with clock value 
which is visible at NMEA-sentences.

What version of MyTracks are you using? 2.0.2
On what version of Android? ICS 4.0.4
On what phone? Samsung Galaxy S3

If possible please provide a log by uploading here.
Detailed instructions can be found here:
http://code.google.com/p/mytracks/wiki/HowToReportErrors

Please provide any additional information here:
How I see it, MyTracks should use GPS clock as a timestamp reference and 
calculate difference of systemtime to GPS-time. This way all sensordata 
timestamps could be fixed to GPS-time and have all GPS-based equipment 
synchronized.

Original issue reported on code.google.com by jori.ham...@gmail.com on 11 Oct 2012 at 6:17

[GoogleCodeExporter]

Naturally GPS time should be fixed with leap seconds to get real world 
UTC-time. Also it would be nice to have "export to GPX" with selectable items 
for timestamp, like second resolution or millisecond resolution.

Original comment by jori.ham...@gmail.com on 12 Oct 2012 at 1:05

[GoogleCodeExporter]

For each track point, My Tracks does use the timestamp from the GPS data.

Original comment by jshih@google.com on 10 Nov 2012 at 6:57

• Changed state: Intended