This is almost entirely incorrect.
Modern GPS use at a minimum 3 GPS satellites to get a Lat/Long fix, called 2D. It needs 4 to get a 3D fix, which gives altitude as well. However, most modern receivers are 12 channel, which means they continuously calculate position based on 12 satellites at the same time.
iPhones, and I would guess smart phones in general, use something called
Assisted GPS. When you are in an area that has cell reception, the cell towers assist in giving position. But in an area without cell towers, you phone uses an internal GPS. You can download apps to look at this data. This will show up typically as a circular grid with each in view satellite listed and sometimes what the signal strength is. If smart phones did not have GPS chips installed, GAIA, OnX and other would now work.
I have preformed comparisons with stand alone GPS units (including professional and very expensive ones I used to use) to iPhones and the iphone has a very impressive GPS in it. I would say that with a fairly decent skyview, you would get a <5 meter accuracy. Not bad considering it has a small internal antenna.
For GPS, the antenna is a very important thing. I tend to use stand alone GPS unit that either have a visible antenna, like a little bump or rod sticking out, or at least the ability to connect an external antenna.
As for why your smart phone is not receiving GPS, I wonder if your privacy setting are not allowing the app to communicate with the GPS. Which app are you using.
