NSUserDefaults values becoming nil - iphone

Question

I am observing strange behaviour of NSUserDefaults. During testing on iphone 4(32-bit) it is working fine. When i send the same app to my client using iPhone 5S(64-bit), NSUserDefault values are becoming nil. Is the behaviour of NSUserDefaults is changing on 32-bit and 64-bit ios versions? I have also used [[NSUserDefaults standardUserDefaults]synchronize] after saving values in NSUserDefaults.I am observing this kind of behaviour from ios 7.1 versions.
AppDelegate.m
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
//to stop updating locations in subsequent launches
if (![#"1" isEqualToString:[[NSUserDefaults standardUserDefaults]
objectForKey:#"aValue"]]) {
//Action here
NSLog(#"LOCATION IS ON");
locationManager = [[CLLocationManager alloc] init];
locationVC = [[LocationVC alloc]init];
[locationVC InitializeWith:_managedObjectContext LocationManager:locationManager];
//[locationVC InitializeWith:_managedObjectContext LocationManager:nil];
}
else {
NSLog(#"LOCATION IS OFF");
locationManager = [[CLLocationManager alloc] init];
locationVC = [[LocationVC alloc]init];
//[locationVC InitializeWith:_managedObjectContext LocationManager:locationManager];
[locationVC InitializeWith:_managedObjectContext LocationManager:nil];
}
}
LocationVC.m
LocationVC *locationVC;
-(void) InitializeWith:(NSManagedObjectContext *)context LocationManager:(CLLocationManager *)locationManager{
//to update location during first launch
if (![#"1" isEqualToString:[[NSUserDefaults standardUserDefaults]
objectForKey:#"aValue"]]) {
[[NSUserDefaults standardUserDefaults] setValue:#"1" forKey:#"aValue"];
[[NSUserDefaults standardUserDefaults] synchronize];
NSLog(#"LOCATION IS ON");
self->locationManager=locationManager;
self->locationManager.delegate = self;
self->locationManager.desiredAccuracy = kCLLocationAccuracyBest;
self->locationManager.distanceFilter = kCLDistanceFilterNone;
[self->locationManager startUpdatingLocation];
_managedObjectContext=context;
}
//in subsequent launches
else{
NSLog(#"LOCATION IS OFF");
_managedObjectContext=context;
[self->locationManager stopUpdatingLocation];
}
}
In my client's iPhone 5S(64-bit), location icon is reappearing after 10 minutes eventhough i have called [self->locationManager stopUpdatingLocation]; in subsequent application lauches.

Answer 1

Is the behaviour of NSUserDefaults is changing on 32-bit and 64-bit ios versions?
No, NSUserDefaults (based on property lists) are designed to be platform independent. You can even copy a binary plist file from a Power PC Mac to an Intel machine, an iPhone 32 bit, or iPhone 64 bit and the file will always produce identical results.
The NSUserDefaults class is known to be very robust.
It's very likely that the error is in your code. If you need more help, please provide more information about how you detect and reproduce the error.
Edit: It seems that you used the wrong method to set #"aValue":
[[NSUserDefaults standardUserDefaults] setValue:#"1" forKey:#"aValue"];
The correct method to set preferences is -setObject:forKey:.
setValue:fortKey: is part of KVC and is not documented to do something specific in NSUserDefaults. While it seems that in current implementations (iOS 7.1) NSUserDefaults overrides setValue:forKey: that's an undocumented feature not guaranteed to work as expected.