Objective-C Library

Base64 Encode
  -NSDataAdditions.h
  -NSDataAdditions.m
  -NSStringAdditions.h
  -NSStringAdditions.m

+ usage

NSData to base64 NSString

NSData *data       = [NSData dataWithContentsOfFile:fileName]; // load some data
NSString* b64str   = [NSString base64StringFromData:data length:[data length]];


base64 NSString to NSData

NSData *decodeData = [NSData base64DataFromString:b64str];

from Any base64 library on iphone-sdk?
(http://stackoverflow.com/questions/392464/any-base64-library-on-iphone-sdk)