Why requestWhenInUseAuthorization doesn't prompt the user for access to the location?

In my viewDidLoad method I have

locationManager = [[CLLocationManager alloc]init]; // initializing locationManager
locationManager.delegate = self; // we set the delegate of locationManager to self.
locationManager.desiredAccuracy = kCLLocationAccuracyBest;
[locationManager startUpdatingLocation];
    
    
if([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0) {
    [locationManager requestWhenInUseAuthorization];
}

And the request is called, but the user is not prompted? Why?

You probably need to update your plist file. Here's a tutorial how to do it, quick & dirty:

You need to do is to add one of the following keys to your Info.plist file:

NSLocationWhenInUseUsageDescription

NSLocationAlwaysUsageDescription

You also need to request authorization for the corresponding location method, WhenInUse or Background. Use one of these calls:

[self.locationManager requestWhenInUseAuthorization]
[self.locationManager requestAlwaysAuthorization]

There's also a post that I found helpful:

https://stackoverflow.com/questions/24062509/location-services-not-working-in-ios-8

This answer details how to update your plist file:

> Add one of the following lines to your info.plist > > > > NSLocationWhenInUseUsageDescription > The spirit of stack overflow is coders helping coders >
> NSLocationAlwaysUsageDescription > I have learned more on stack overflow than anything else

You'll probably want to customize and spell-check the strings of the dictionary entry that goes in the info.plist file before shipping the code.