How accurate is the iPhone GPS (in radius)?

Question

I want to know how accurate our GPS is on the iphone 4 / 4S, because my new project uses gps to track something. I mean the exact indicator about a meter. I have another question, like mine, but I have no answer. Is it possible to track the radius for only 1 meter? How long is the accuracy that the iphone 4 / 4s gps has (at least)? 10 meters? how about 1 meter? can it track a radius of 1 meter? oh, my next project for my company is an outdoor application. I know that I can check it myself, but get an answer from here faster. thanks.

Answer 1

The simple answer is: No, this is not exactly up to 1 m.

In some cases, although this is so, do not count on it. In the urban landscape, sometimes I am crowded out by about 20 meters. But it seems that all the devices get the same offset, so you can determine whether they are close or not.

Edit: I have to say that I have worked a lot with location services on the iphone, so I am absolutely sure of this answer.

Answer 2

I tested 4S using a standard GPS test to position the device at a known point (viewpoint - 1 cm accuracy) for a certain period of time. This 30-minute continuous test was conducted in Tucson, Arizona (good GPS territory) compared to New York (tall buildings and further north) using GPS Photo-Link. Thus, we usually look at 10-meter accuracy, which means that 92% -97% of the points are within 10 meters of the NSEW known level. The iPhone did not pass the first test, so I quit the results and stopped testing it. I'm waiting for WAAS on phones to see how phones improve GPS, but I think most phone companies are going to throw their money in improving the camera.

Answer 3

Well maybe you can set the desired accuracy as

CLLocationManager *locationManager = [[CLLocationManager alloc] init]; locationManager.delegate = self; locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters; locationManager.distanceFilter = 10; [locationManager startUpdatingLocation]; 

See Apple documentation for more information. Hope this helps you. good luck.