I have two different versions. Both involve live tracking. One plugs into the OBD port of the truck, and is easily installed. It is also easily removed, but I haven't had to fire anyone for that, yet. IT is about $25 a month.
The other is tied into the camera system on my trucks. Because of what we do, I am able to record a full days labor, view live online at anytime, and generally monitor and be a nanny to my guys, whenever I feel like it. It has proved expensive, but advantageous. It costs me an exorbitant amount for the time we really use it, but in reality, I have found it worthwhile. It does drive me absolutely nuts when it fails at an inopportune time. I have had that happen. It is also helpful when someone calls in on one of my guys to complain, and we are able tow quickly observe the interaction to see if our guy was behaving inappropriately. Just for grins and giggles, I think that out of hundreds of calls, there was only one time that our guy was in the wrong. The rest were just people trying to cause problems for whatever reason.