Okay from what I found until now:
- There are some Chinese trackers which can be "hacked" and with some effort programmed using the Arduino IDE (none provide code, all are reverse-engineered)
- Some people tried to create an OS tracker and their Kickstarter campaign failed
- All commercial products want to talk to their sellers
- Garmin seems to be the least talkative?
- You can spend 900-2000 EUR for Garmin smart-watches (The fuck?)
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