NSUserDefaults or keychain is better to save username and password in iPhone app

In my iphone app there is some confidential data like username, password and some urls to a webservice. Which one is better NSUserdefaults or keychain. Somebody says NSUserdefaults is insecure. Why it is insecure? and can any one give the pros and cons of each one.

Solution 1:

NSUserDefaults is quite easy to use and stores one value per key only. But apparently, it is not a very secure method, as there is no encryption.

But the Keychain is secure, though it is a bit hard to code. You can refer these link to use keychain access.

http://log.scifihifi.com/post/55837387/simple-iphone-keychain-code

you can also use this library deviced by Simon

https://github.com/goosoftware/GSKeychain

I hope it helps you!!

Solution 2:

It may be useful to notice that Keychain data will be persisted even if you app is deleted, but NSUserDefaults data will go away with the app (NSUserDefaults is part of the app sandbox, Keychain is an app-independent service).