NBPhoneNumberUtil *phoneUtil = [NBPhoneNumberUtil sharedInstance];
 NSError *anError = nil;
 NBPhoneNumber *myNumber = [phoneUtil parse:@"6766077303"
                              defaultRegion:@"AT" error:&anError];
 if (anError == nil) {
     NSLog(@"isValidPhoneNumber ? [%@]", [phoneUtil isValidNumber:myNumber] ? @"YES":@"NO");

     // E164          : +436766077303
     NSLog(@"E164          : %@", [phoneUtil format:myNumber
                                       numberFormat:NBEPhoneNumberFormatE164
                                              error:&anError]);
     // INTERNATIONAL : +43 676 6077303
     NSLog(@"INTERNATIONAL : %@", [phoneUtil format:myNumber
                                       numberFormat:NBEPhoneNumberFormatINTERNATIONAL
                                              error:&anError]);
     // NATIONAL      : 0676 6077303
     NSLog(@"NATIONAL      : %@", [phoneUtil format:myNumber
                                       numberFormat:NBEPhoneNumberFormatNATIONAL
                                              error:&anError]);
     // RFC3966       : tel:+43-676-6077303
     NSLog(@"RFC3966       : %@", [phoneUtil format:myNumber
                                       numberFormat:NBEPhoneNumberFormatRFC3966
                                              error:&anError]);
 } else {
     NSLog(@"Error : %@", [anError localizedDescription]);
 }

 NSLog (@"extractCountryCode [%@]", [phoneUtil extractCountryCode:@"823213123123" nationalNumber:nil]);

 NSString *nationalNumber = nil;
 NSNumber *countryCode = [phoneUtil extractCountryCode:@"823213123123" nationalNumber:&nationalNumber];

 NSLog (@"extractCountryCode [%@] [%@]", countryCode, nationalNumber);

// Manually added
#import "NBPhoneNumberUtil.h"
#import "NBPhoneNumber.h"

// CocoaPods (check your library path)
#import "libPhoneNumber_iOS/NBPhoneNumberUtil.h"
#import "libPhoneNumber_iOS/NBPhoneNumber.h"

// add more if you want...

 NBAsYouTypeFormatter *f = [[NBAsYouTypeFormatter alloc] initWithRegionCode:@"US"];
    NSLog(@"%@", [f inputDigit:@"6"]); // "6"
    NSLog(@"%@", [f inputDigit:@"5"]); // "65"
    NSLog(@"%@", [f inputDigit:@"0"]); // "650"
    NSLog(@"%@", [f inputDigit:@"2"]); // "650 2"
    NSLog(@"%@", [f inputDigit:@"5"]); // "650 25"
    NSLog(@"%@", [f inputDigit:@"3"]); // "650 253"

    // Note this is how a US local number (without area code) should be formatted.
    NSLog(@"%@", [f inputDigit:@"2"]); // "650 2532"
    NSLog(@"%@", [f inputDigit:@"2"]); // "650 253 22"
    NSLog(@"%@", [f inputDigit:@"2"]); // "650 253 222"
    NSLog(@"%@", [f inputDigit:@"2"]); // "650 253 2222"
    // Can remove last digit
    NSLog(@"%@", [f removeLastDigit]); // "650 253 222"

    NSLog(@"%@", [f inputString:@"16502532222"]); // 1 650 253 2222