Comments on: Detecting Bad CoreLocation Data

By: Andrew Hawken

Andrew Hawken — Sun, 13 Jun 2010 18:32:58 +0000

I think I can take this information one step further. You should not just ignore but blacklist any points that appear out of order, and then drop any further references to that exact location: that seems clear out the repeated jumps to a specific point I see quite often.

By: ultrasound technician

ultrasound technician — Tue, 01 Jun 2010 03:47:27 +0000

nice post. thanks.

By: genesis

genesis — Thu, 01 Apr 2010 13:53:23 +0000

You have tested it and writing form your personal experience or you find some information online?

By: Manuel Binna

Manuel Binna — Mon, 08 Feb 2010 08:53:45 +0000

Hi Troy,

as always, another great blog post! But are you sure that points, that are not in order should be filtered out? The iPhone Application Programming Guide says in chapter 8 “Getting the User’s Current Location”:

“Note: The Core Location framework records timestamp values at the beginning of each location query, not when that query returns. Because Core Location uses several different techniques to get a location fix, queries can sometimes come back in a different order than their timestamps might otherwise indicate. As a result, it is normal for new events to sometimes have timestamps that are slightly older than those from previous events. The framework concentrates on improving the accuracy of the location data with each new event it delivers, regardless of the timestamp values.”

Greetings from Germany,
Manuel