GPS Tracking

Satellite status, recording a track in the background, the accuracy gate, and averaging a GPS point.

Satellite status

Signal strength per satellite, grouped by constellation: BeiDou, Galileo, GPS, QZSS and GLONASS. The header sums it up: satellites used, average C/N0, the three DOP figures, and the accuracy the receiver is reporting.

Open it by long-pressing the accuracy chip in the GPS bar. A green bar is a strong signal, and a tick means the satellite is being used in the fix. Indoors or under a roof the list comes up empty and the fix is whatever the last outdoor position was, so walk outside before you trust the chip.

Tracking modes

Mode	Reads	A point every	Battery, roughly
High Precision	the raw GPS receiver	1 m	~15 % an hour
Balanced (default)	the fused provider	5 m	~8 % an hour
Battery Saver	the fused provider	10 m	~5 % an hour

Set in Settings › GPS. The mode decides which receiver is read and how far you have to move before a point is kept. It does not decide how accurate a point is; that is down to the sky and the receiver, and the chip shows you what they managed. The fused provider blends GPS with Wi-Fi and cell for a faster first fix. High Precision reads the raw receiver instead, which is the only way past the 10 m or so that fused positions tend to settle at. The mode applies to the track; placing a point always uses the best fix going at that moment.

Some phones will not give the fused provider to an app in the background. When that happens the track is recorded from the raw GPS receiver instead and you will not notice the difference. The Map page says Not recording only when neither one can be read.

Recording the track

Thirteen minutes in: the trail follows the campus road, 16 points and 80 m so far. The compass arrow is your position and heading, and the rail on the right holds the tools.

A minute later, with the camera used on the way: photo and video markers sit on the track where they were taken.

The track records in the background for as long as the survey is running: screen off, phone in a pocket, another app in front. A notification stays up the whole time. Stopping the survey stops the track, and resuming it carries on with the same one.

The accuracy gate

The chip in the GPS bar shows the reported accuracy, and its colour tells you whether to wait: green is good, amber will do, red means hold on. Every photo, video and point carries the accuracy it was captured with, and the export keeps it in the accuracy column.

GPS averaging

Forty fixes averaged where ten were needed. The sheet calls the position stable once the mean has moved less than 50 cm over the last ten fixes. The ±4.2 m is the larger of the reported mean and the spread, and the dot plot shows where the fixes landed, the newest ones brightest.

For a corner that has to be right, tap the GPS average tool while placing a point. The app gathers fixes as you stand still, throws out the worst of them, and reports the averaged position, its spread (RMS) and the reported accuracy as separate figures. Use this position puts the point at the mean.