Now I am carrying a dedicated Android phone with me (a Xiaomi Mi 11 Lite 5G) on which I have PhoneTrack [2] installed. The app starts tracking as soon as the phone is moving and saves all the data on device. I used to have an instance of Owntracks [3] running, but now I just run a simple Flask app which pipes the GPS points to a PostGIS database on my local network when I am home. To visualize the tracks, I import them into QGIS. As the phone is solely used for tracking and only when I take it with me, the battery lasts about three days.
[1] http://www.transystem.com.tw/www/product.php?b=G&m=pe&cid=4&... [2] https://f-droid.org/en/packages/net.eneiluj.nextcloud.phonet... [3] https://owntracks.org
The plus version is on F-Droid for free. It has unlimited map downloads.
If you look at Google Timeline, sometimes the track it records is not particularly accurate, likely because it's only getting updates for significant changes in your location.
I also use OwnTracks to keep track of myself, and there I can see the individual points it gets from the OS notifying it of location changes, and... it's honestly not that great sometimes.
The positions from OSMAnd seem pretty spot on.
I had no idea it did this. Thanks for the tip!