In order to access the internet through the Facebook Login asking for a Check-in, users have to follow these steps:
STEP 1
The user clicks on the Facebook Login button in the splash page:

STEP 2
The user logs into Facebook, if he is not already logged:

STEP 3
The user allows or disallows the application to collect the following information: Public profile, email address, date of birth and location:

STEP 4
The Check-in form appears and user decides if to proceed with Check-In social action or Skip it :

STEP 5
If user prefers to continue with Check-in action, the application asks to write a post (1), to choose where to share it (2), and who should see the post (3). By clicking on "Post su Facebook" it is possible to go ahead and access the internet.

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Facebook social actions overview