Use NSSearchPathForDirectoriesInDomains(). First argument “NSDocumentDirecotry” is the key to specify special directory, in this case Document directory under the application. The method returns absolute path expression.
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,
NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSLog(@"NSDocumentDirectory is %@", documentsDirectory);