As I'm aware it is not possible (since Facebook API v2.0) to get a list of all Facebook friends of a Facebook user. It is just possible to get all friends of a user who already use the same app.
I searched the web and found the following links which confirm my hypotheses:
- https://stackoverflow.com/a/23926468/1325107
- Graph API Explorer
- https://developers.facebook.com/docs/apps/faq#friend_invite
So, in v1.0 it was possible, but the option to get a list of all friends of a user is not possible anymore since v2.0
BUT: How is it possible for an app like Kiwi, to invite all Facebook friends in the background? If I install the app, and if I log in with Facebook, I can see clearly the "friend_list" permission, which gives Kiwi the ability to invite all Facebook friends without asking. Why is the "friend_list" permission possible for Kiwi? It can't be because they use v1.0, since this version is not available anymore as of April 2015. On developers.facebook.com I'm not able to enhance my app with the "friend_list" permission, because it is not available in the list of permissions to choose from.
Thank you.