GPS Tracking is a contentious issue, even more when it is forced on the subject. There are however situations where we can be legally obligated to subject ourselves to such tracking (for example when we are using the car of the employer or if our legal guardian wishes so). The LandAirSea company specializes in such tracking systems. They provide a variety of models, some with real-time tracking capabilities, others requiring the physical re-acquisition of the equipment for later analysis. For example we have the tracking key (available also on Amazon – disclosure: the link contains my affiliate ID), a very small form-factor solution with mostly positive reviews.
The company has been around since 1994, so, as the old cliché says, they must be doing something right. One positive aspect I observed is that tracking seems to be free for many models, there are no additional recurring costs besides the purchasing of the GPS. On the downside (if this is a concern for you), the real-time tracking seems to be limited to the mainland of USA. In conclusion: good company, nice offer and it is worth considering if you are shopping around for such equipments. One thing to keep in mind is that GPS units can be quite slow to acquire the signal in my experience (up to a couple of minutes if it isn’t moving, and even more if the unit is in motion).
Full disclosure: this is a paid review from ReviewMe. Under the terms of the understanding I was not obligated to skew my viewpoint in any way (ie. only post positive facts).