Yes, I agree, it could very well be used for bFound Mobile. This is one of the interesting things about sensors and software - just a slight change in the "sensed" information or the way it is collected and utilized, with potentially a completely different "app" software (or even a somewhat slight variation)... and you have a whole different product.

But yes, this could definitely be used for that application. In order to do so, IMO the most functional solution would involve the phone app being used to receive heading "progress" data, and then resolve that data into location updates which it would then record kind of like map waypoints. In this way, the phone app would then know the location of the device (and vehicle) at any time, relative to the last "known/verified" GPS position/location.

Of course, all of this depends on whether I am right about the entire board being a IMU device, and the "U2" IC being the IMU sensor. It's really difficult to know for sure, as you cannot even see the U2 component very well. But everything sure fits the scenario I laid out in my previous post.