current date
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
formatter.dateFormat = @"yyyy-MM-dd HH:mm";
NSString *currentDate = [formatter stringFromDate:[NSDate date]];
unix timestamp
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"yyyy-MM-dd hh:mm:ss"];
NSDate *date = [NSDate dateWithTimeIntervalSince1970:1402418789];
NSString *formattedDateString = [dateFormatter stringFromDate:date];
// 2014-06-11 12:46:29
NSLog(@"formattedDateString: %@", formattedDateString);
// convert to unix timestamp
NSlog(@"timestamp=%f",[[NSDate date] timeIntervalSince1970]);