Locale-Sensitive Objective-C Method

NSCalendar setTimeZone:
NSDateComponents setTimeZone:
NSDateFormatter setTimeZone:

For NSCalendar setTimeZone, click here for Apple Developer Documentation details.
For NSDateComponents setTimeZone, click here for Apple Developer Documentation details.
For NSDateFormatter setTimeZone, click here for Apple Developer Documentation details.

For information about Objective-C Internationalization, click here.