It seems like the only way I can add a fan page “like” button is to use UIWebView.
I personally don’t like this method and I’d much prefer to be able to like the page via the Graph API, similarly to what explained here: https://developers.facebook.com/docs/howtos/publish-to-feed-ios-sdk/
In this question
the last answer by ToddH was that it’s possible to “like” a fan page via the Graph API. According to Stan’s answer however, it seems like you can’t like a fan page via the Graph API, as it’s against Facebook’s platform policies, but you can like via Open graph (which I haven’t used yet).
In short: Can I use Graph API to like a fan page? If not is my only option is to use UIWebView (as explained in Ray’s tutorial), or I have a new option to use Facebook’s Open graph? (please elaborate on this option if it’s legit)
EDIT: the short answer is no, you can’t use Graph API/Open Graph to like a fan page. See my answer below.
Also I want to add that I don’t understand why it was so important to down vote this question.
As Igy, who works at Facebook, wrote in the comments above, there is no way to do it directly via Graph API nor via Open Graph.
In my project I have added a button when clicked navigates to the facebook fan page via UIWebView and from there the user can Like the page.