Why does my GPS location move around when I’m sitting still?

GPS works by receiving signals from satellites orbiting the Earth. Your phone calculates its position by measuring tiny differences in the time it takes those signals to arrive. Under ideal conditions — outdoors with a clear view of the sky — this is surprisingly accurate, usually within a few meters.

But when conditions aren’t ideal, those position calculations start to drift. The most common causes are being indoors (walls, roofs, and windows weaken and reflect satellite signals), urban areas where signals bounce off buildings, and simply having fewer satellites in view due to terrain or obstructions. When this happens, your phone’s reported location can jump around by tens or even hundreds of meters, even though you haven’t moved at all.

This is a fundamental limitation of how GPS works. It’s not a bug in Cadence or your phone. Every GPS-based app experiences this.

Cadence does filter out GPS readings that look unreliable, but there’s a limit to how aggressively it can do this. If it throws out too many data points, it risks removing real movement too. So if your signal stays poor for a while, some of that drift will eventually get recorded.

A few things that help

If you’re stopped for a while, like at a rest stop, waiting at a light, or sitting inside, turning on Auto Pause While Stopped on the Cadence > Settings screen will prevent Cadence from recording GPS drift as actual distance. This is the single most effective thing you can do.

Once you’re moving outdoors with a clear sky, GPS accuracy improves dramatically and the drift largely goes away.

If you notice drift at the start of an activity, give your phone 30 seconds or so outside before you begin. This lets it lock onto more satellites and settle on a more accurate position.