How to use Keychain for saving password like GenericKeychain sample code

I want to save user's id and password in App.

What is recommendable encryption way when I save id and password.

I'm finding more safe way from Jailbreak or Hacker.

How about GenericKeychain sample code ?

http://developer.apple.com/library/ios/#samplecode/GenericKeychain/Introduction/Intro.html#//apple_ref/doc/uid/DTS40007797

I can't have confidence about safe how to use Keychain like GenericKeychain sample code.

Please tell me some advices. Thank you ^^*