I still find working with dates in iOS a little tricky. There is always a new format to deal with and it’s all about getting the identifiers for the format just right! I recently ran into ISO8601 and hope the bit of code below is of some use.
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ssZZZZZ"];
NSDate *date = [dateFormatter dateFromString:self.releaseDate];
[dateFormatter setDateStyle:NSDateFormatterLongStyle];
self.dateString = [dateFormatter stringFromDate:date];
You can, of course, pick any other date format style (instead of Long) as the output. As always, let me know if you have any questions.