You can set it to update location every minute, hour, ten seconds etc. Then just check the app for last known location. I have excellent telecom coverage where I live, and it can ping for wifi networks as well as gps, so I have personally never lost signal as long as it’s charged.
The frequent charging might be the biggest downside for tracking a bike, for my pet I can just do it every night when they stay indoors and don’t need it.
My pet tracker can be set up to only send location when asked for it. It uses a SIM card (pre paid), plus you can call it to listen to the surroundings or have it blink or make noise through the app.
The app requires the phone numbers of the people who are allowed to query the tracker.
I don’t know what trackers are available in your country. I found several who had subscription-type deals to have the tracking actually work. I hate subscriptions, so will always choose to pay more upfront to control my usage and cost. It’s a lot more expensive than any sort of air tag.
With the one I have I can delete the app after setup and only text the number to get gps-coordinates when I wish, but the app works great for my needs.
It also triangulates with WiFi etc to give a more accurate reading. All such settings can be changed in the app.
Can’t speak for privacy aside from it can be set up to only send info when queried and only to preselected numbers. Kinda depends what you mean by privacy respecting.
It does need to charge (varies greatly depending on weather, queries, settings etc) often.
Many countries have some sort of Romeo & Juliet-laws where teenagers of a certain age are allowed to have sex with each other/in their age brackets but adults are not allowed to have sex with minors.
Is that the case, or is 40+ and 15 good and legal?