Perhaps this one just works really, really well- and it does- given that iDevices facilitating making it work are everywhere?
I picked up a few of these for car and bike, mostly as some kind of bit of hope that should either get stolen, I might be able to use this to help track it down. I'm STUNNED at how well the whole system works. Away from the car in a public lot one day for hours and I just took a few peeks from time to time to see that location was (usually) "updated minutes ago" over and over.
Ironically(?), I wish these did NOT have the little speaker, as I wouldn't want to make it easy for the car or bike thief to find them when they are doing the crime. And yes, I'm aware of how to open them up and remove the speaker... and will likely want to do that soon.
The much smaller competitors may have equally good tracking toys but perhaps the system doesn't work as well overall.
AND, of course, big names yields big news yields big voter attention. For example, thousands of individual traders likely engage in some level of insider trading every month but only the occasional bigger name- like Martha Stewart- seems to get prosecuted. Why? Because politicians/agencies want to show that they are doing SOMETHING and news is a free way to do that. Prosecute Noname Smith for insider trading and you might not even get a news story about it. Prosecute a celebrity and you'll likely get a lot of free PR.
Go after Apple for anything and that will get big news that the GOV is doing something. Go after the micro, NoName Corp that has only 1000 trackers in the wild and there will be no news in that. Same energy, very different PR result.