iPhone App Satellite GPS view

April 29, 2013 10:19 AM

Hi Everyone I would like to see a list of all the GPS and Glosnass that my iPhone 5 is receiving with their signal strength. I have searched but cannot find. (This is similar to a app on the Garmin GPS) Thanks BB
posted by bright77blue to Technology (6 answers total)

The phone does not make this information available to apps, unfortunately. I think a vertical and horizontal accuracy is the most information you will ever see.
posted by ftm at 10:27 AM on April 29, 2013

Yeah, the satellite information is not available to iOS apps from the CoreLocation API. I don't think it's even available with a jailbreak: at least, a couple of related questions come up with no answer. There is some third party GPS hardware that has a private API for accessing their satellites; Bad Elf, for instance. But nothing on the stock iPhone.

In urban environments the iPhone pretty much never uses the GPS radio anyway; cell tower and wifi location work better. And the location API does return a fairly useful precision measurement.
posted by Nelson at 10:50 AM on April 29, 2013

The GPS hardware outputs a text stream in the form of NMEA sentences, which can contain the IDs of the satellites that are transmitting. Here's the schema for the GPTRF sentence. If you can listen for this output (there's a lot of it; you have to deal with it efficiently), you can look up the ID for info about the satellites. Unfortunately, iOS doesn't give you access to that (as far as I can tell).

If you plug in an external GPS module, like this, you can theoretically write software that consumes the NMEA data. Or you can switch to Android.
posted by klanawa at 1:08 PM on April 29, 2013

Um... or what Nelson said.
posted by klanawa at 1:09 PM on April 29, 2013

You could write a hacky device-specific app to run on your own phone that addresses the hardware directly and gets this info. Apple would never allow it in the app store though. Such an app may already exist over in the outlaw jailbreak world.
posted by w0mbat at 2:45 PM on April 29, 2013

Huh, that's too bad. GPS Test on my Android phone is really cool!
posted by intermod at 10:29 PM on April 29, 2013