[TomVDB]

> Isn't this exactly what aGPS is? One or more data points outside of satellite data?

I don’t think that’s what it is: with aGPS, the phone downloads data of where the satellites are. That allows the phone to accelerate its ability to lock onto GPS satellites.

Triangulation based on cell phone tower location is orthogonal to aGPS. The original iPhone didn’t have a GPS receiver and didn’t use aGPS, so it used the location of the towers as a crude way to figure out its location.

The triangulation + 2 satellites examples could be (but doesn’t have to be) a hybrid of the 2:

Use old school triangularion as one of the location estimates and use 2 satellites as further location estimates.

And then, orthogonally and optionally, you could use aGPS to accelerate finding additional satellites.