There are a few open source ones: https://www.traccar.org/ https://www.traccar.org/ https://owntracks.org/ https://owntracks.org/ https://apps.nextcloud.com/ap

There are a few open source ones: https://www.traccar.org/ https://www.traccar.org/ https://owntracks.org/ https://owntracks.org/ https://apps.nextcloud.com/apps/phonetrack https://apps.nextcloud.com/apps/phonetrack (if you have a nextcloud) The nextcloud one is by far the lightest on my phone battery, the other ones would often use very much battery. But i use android and YMMV.