I've been working on a location based app recently and am noticing some strange values for CLLocation. I often get a horizontalAccuracy
of 1414
and a verticalAccuracy
of -1
. Any clue what this indicates? As far as I can tell, these points are often very accurate. What is the difference between verticalAccuracy and horizontalAccuracy?
The -1 for verticalAccuracy
indicates that the altitude in the CLLocation
is not valid. You only get altitude with a 3D GPS position.
The 1414 for horizontalAccuracy
indicates that the horizontal (lat/lon) position could be up to 1414m off (this is just an estimated error). This is probably a location determined by cell tower triangulation or WiFi location data. GPS locations usually report 100m or better.
To get a higher accuracy location (300m or better) you need to set desiredAccuracy
and wait for the GPS receiver to lock onto at least 3 satellites (or 4 for a 3D fix). Until that happens CLLocationManager
will give you the best it has which is WiFi or Cell tower triangulation results.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With