>I'm hoping for precise indoor navigation, Google and Apple are currently working on that. All you'd have to do is walk around with your phone, measuring signal strength and then visualize that.

I'd wager there are _a lot_ more folks that that looking the problem. Its difficult to just use signal strength as this is heavily multi path dependent and time-varying as anything (e.g., moving your phone and hand around) within the environment changes.

There are results in the literature floating around that show some basic success, but nothing at all like the dreams of indoor GPS we're all hoping for. It's a fun problem space, but still in its infancy.