CLLocationManager code for ios8 isn't working in ios7 - ios7

Question

Previously I used a simple code(which I not posting here) for gps tracking, which works perfectly fine on iPhone 4. Currently I'm using the following code in viewcontroller.m for getting current gps location:
- (void)viewDidLoad {
[super viewDidLoad];
[self CurrentLocationIdentifier];
}
-(void)CurrentLocationIdentifier
{
locationManager = [CLLocationManager new];
locationManager.delegate = self;
locationManager.distanceFilter = kCLDistanceFilterNone;
locationManager.desiredAccuracy = kCLLocationAccuracyBest;
if (IS_OS_8_OR_LATER)
{
[locationManager requestWhenInUseAuthorization];
[locationManager requestAlwaysAuthorization];
}
if ([locationManager respondsToSelector:#selector(requestWhenInUseAuthorization)]) {
[locationManager requestWhenInUseAuthorization];
}
[locationManager startMonitoringSignificantLocationChanges];
}
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{
current = [locations objectAtIndex:0];
[locationManager stopUpdatingLocation];
CLGeocoder *geocoder = [[CLGeocoder alloc] init] ;
[geocoder reverseGeocodeLocation:current completionHandler:^(NSArray *placemarks, NSError *error)
{
if (!(error))
{
CLPlacemark *placemark = [placemarks objectAtIndex:0];
NSLog(#"\nCurrent Location Detected\n");
NSLog(#"placemark %#",placemark);
NSString *locatedAt = [[placemark.addressDictionary valueForKey:#"FormattedAddressLines"] componentsJoinedByString:#", "];
NSString *Address = [[NSString alloc]initWithString:locatedAt];
NSString *Area = [[NSString alloc]initWithString:placemark.locality];
NSString *Country = [[NSString alloc]initWithString:placemark.country];
NSString *CountryArea = [NSString stringWithFormat:#"%#, %#", Area,Country];
NSLog(#"Address: %#", Address);
NSLog(#"CountryArea: %#",CountryArea);
}
else
{
NSLog(#"Geocode failed with error %#", error);
NSLog(#"\nCurrent Location Not Detected\n");
}
}];
}
I Used this link to support gps tracking for iPhone 6.This code fetches current gps location on iPhone 6 and iPhone 4S but not in iPhone 5S and iPhone 6 Plus.I'm wondering why this is happening?