Looking for a "passive" GPS tracking device. Everything I have found on the market is obsolete and overpriced, especially compared to the "active" trackers that are essentially cellular devices that respond and/or broadcast their location. The drawback to an active device is that it typically requires a data contract and is much more traceable.

The best of the bad options I have found in the passive arena is the Tracking Key but it is widely panned because LAS's products are not weather-sealed ("just put it in a plastic bag" is their suggestion), their support is abysmal, and all cost at least $150! (There's no question that in volume a controller, GPS module, USB interface, battery, magnet, and rubberized jacket should command a market price of at most $100.)

Looking for a passive GPS tracker with the following features:

  1. Weather sealed
  2. (Optional) magnetic attachment
  3. Antenna works when installed under a vehicle
  4. Battery-efficient: I.e., it goes to sleep when not moved for a certain period.
  • 1
    What kind of battery-autonomy do you envision?
    – Stefan
    Commented Nov 18, 2015 at 15:17
  • @Stefan - Not sure I understand the question. Obviously the device has to contain its own power source. Whether that's an embedded rechargeable or whether it accepts disposable batteries doesn't matter to me.
    – feetwet
    Commented Nov 18, 2015 at 15:51
  • 1
    Well, the question is: do you need the battery to last 2h? 2days? 2months?
    – Stefan
    Commented Nov 18, 2015 at 15:53
  • 1
    @Stefan - That would depend on usage. I suppose at a minimum the battery should be sufficient to log 24 hours of continuous movement. For a typical person or vehicle would be a week or two of recording.
    – feetwet
    Commented Nov 18, 2015 at 15:59
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    @AdamWykes - Well I'm not in the prototyping business. But if there's something better than the kludges of existing products outlined in the question then I would be interested.
    – feetwet
    Commented Sep 10, 2016 at 13:31

2 Answers 2


I just came across a great hybrid (depending on the exact use case): The Automatic Pro plugs into a vehicle's OBD-II port, transmits location updates every 20 seconds when the vehicle is in motion, and draws its power from the car.

Yes, it's an "active" tracker, but the $130 purchase price includes "at least" 5 years of 3G data service.

So it's not exactly what was specified: It's somewhat traceable, it requires access to the inside of the vehicle to place, and it would be readily noticed by anybody checking the vehicle's OBD port ... unless connected and concealed off a splitter cable. But on the plus side it offers real-time tracking, IFTTT, and other integration and safety features.

  • You might be able to hide it inside the dash somewhere if you had time to pop that open and could use an extension cable to run it back from the ODB-II port, but yeah, that's kind of a dealbreaker isn't it? I mean that part of the care is usually highly visible to its driver.
    – Adam Wykes
    Commented Sep 10, 2016 at 2:45
  • @AdamWykes - Most people don't know what an OBD port is, or where it is in their cars. As an added measure of protection a splitter sounds like a great idea: As long as an OBD device can be plugged in where the jack is supposed to be I doubt even repair/service technicians would notice that there's a split leading to concealed device, or that they would consider it noteworthy.
    – feetwet
    Commented Sep 10, 2016 at 13:34

Just came across another option: TrackR are little sub-$30 transponders with a one-year battery life, though apparently they depend on a device running their app to come within 100 feet of the transponder to update its location.

  • Just found another very similar product called Tile.
    – feetwet
    Commented Feb 20, 2017 at 18:15
  • TrackR link is 404. Is it thetrackr.com ? (If so, for giggles, read the FAQ about battery replacement ;-)
    – Mawg
    Commented Mar 18, 2021 at 8:59
  • Just curious, what's the accuracy, in distance? And is there any indication of direction? Since this was posted, BT 5.1+ has introduced Angle of Departure/Arrival allows positioning to within 1cm, including direction. Source
    – Mawg
    Commented Mar 18, 2021 at 9:15
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    @MawgsaysreinstateMonica yep looks like sometime in the last four years TrackR did well enough to afford a .com domain LOL; I updated to that link.
    – feetwet
    Commented Mar 18, 2021 at 17:16

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