iOS7 app backward compatible with iOS5 regarding unique identifier

Question

My app is compatible with iOS5 and iOS6. Until now I had no problem using:

NSString DeviceID = [[UIDevice currentDevice] uniqueIdentifier];

Answer 1

The best and recommend option by Apple is:

 NSString *adId = [[[ASIdentifierManager sharedManager] advertisingIdentifier] UUIDString];

Use it for every device above 5.0.

For 5.0 you have to use uniqueIdentifier. The best to check if it's available is:

if (!NSClassFromString(@"ASIdentifierManager"))

Combining that will give you:

- (NSString *) advertisingIdentifier
{
    if (!NSClassFromString(@"ASIdentifierManager")) {
        SEL selector = NSSelectorFromString(@"uniqueIdentifier");
        if ([[UIDevice currentDevice] respondsToSelector:selector]) {
            return [[UIDevice currentDevice] performSelector:selector];
        }
        //or get macaddress here http://iosdevelopertips.com/device/determine-mac-address.html
    }
    return [[[ASIdentifierManager sharedManager] advertisingIdentifier] UUIDString];
}