# Are GPS coordinates more accurate if they are fetched at a small interval

I've been doing some tests with a self-written application that uses the GPS to report locations and plot them on a map. One of the things I've noticed is that the coordinates seem to be more accurate when the interval at which they are gathered is smaller. In general, when reporting every 10 or 15 seconds the coordinates seem to correlate more with the actual position at that time, whereas when reporting every 30 or 60 seconds they seem to be less accurate.

This is even true for a non-moving phone. If I put it down in my backyard and leave it to gather 10 coordinates, once every 10 seconds, I seem to get coordinates that are less spread out and actually are a pretty good indication of the actual location. When gathering 10 coordinates, once every minute, I get a lot less accurate measurements.

Is there any hard evidence to suggest that gathering coordinates at a small interval is more accurate? Or is what I am seeing just coincidence?

• What's happening during these intervals? If you're in a car or something I would guess that the phone loses sight of more satellites the further you move. Jun 10, 2015 at 13:42
• I've done some tests just walking around, moving about 20-30 meters. But also tried just putting the phone down somewhere and not touch it...
– JDT
Jun 10, 2015 at 13:47
• An easy explanation (no source, so not proven): The shorter the interval, the less the device could have moved. GPS accuracy is not "down to the millimeter", but with shorter intervals errors are easier to compensate. Think of adjusting your time via ntpdate, same principle there: even with a single server given, by default it asks 4 times and then builds the "average" out of the results – while for more accuracy you can have it ask more times before "correlating". However keep in mind: the shorter the interval, the more battery it eats (keyword: WAKE_LOCK). Find a balance.
– Izzy
Jun 10, 2015 at 14:58