Currently Being ModeratedNov 22, 2012 7:24 AM (in response to hoangdoanh)
Using Facebook API should help you to implement custom login. But, if you want to have an easy method you can use Addthis framework, if you need to offer FB logins in older version of IOS (<6). In IOS 6 SDK you have the Social framework and it is good to use it. Just use Facebook API specifications.