[chrisretusn]

Originally Posted by Tsunami

Is it really possible that upon joining a social network, the social network (doesn't matter which) can access one's email account in order to send invites to all contacts in that email account used for signing up? I mean, unless one is clumsy enough to use identical passwords, the social network for which one signs up may know the email address used to sign up by the new member, but the social network doesn't have the actual password of that email account. So how is it possible that they'd send invites and thus know which contacts are in that email account? That'd require actually logging in to the email account used to sign up, which should be impossible without knowing that email account's password.

I cannot see how any social network could access one's email account, as long as that account is not part of that service. Take Google (one access for services) for example. The soon to be shutdown Google+ could gain conceivably gain access to your Gmail Contact list. That said, I do not see any sort of connection between my Google+ and Google Contacts. I don't have any contacts in Google Contacts, but I don't think that is why. I just can't find any connection to Google Contacts from Google+

I do all email from a client (Claws Mail) on this computer, the Gmail App on my cell phone does not have access to my cell phone Contacts.

All of my web base email accounts have similar empty contacts list for the same reason, any App install for that service is denied access to Contact on the cell phone.

My cell phone contacts are quite different than my email contacts.

I site that allows access via a social network service like Facebook or Google

From that Dutch Wkipedia page at the bottom (translated)

Someone who is a member of Badoo can count on personal contacts from an email or Facebook account to be kept informed of this membership. Badoo even looks for contacts on other e-mail or Facebook accounts of its members. Presumably this is done via corresponding passwords.

Is not sourced, I don't see how this citation is possible as stated. Badoo does have a sign up option via Facebook though so I would presume that would give them access to Facebooks Friends list. As for other email, just can't see that happening. Badoo would need the password. I'm not about to sign up for Badoo to test this.