NOTE: Due to changes with the way Facebook allows 3rd party apps to share to users' timelines and business pages, sharing to Facebook has changed.
You can link your Twitter, Facebook, and LinkedIn accounts directly from the PostBeyond mobile apps for iOS and Android.
First, go to your Profile section.
From your profile, go to your settings.
In your settings, select 'Linked Accounts'.
From there, switch on the toggles for any Social Account you would like to connect.
Authenticate your accounts with the social networks.
Once you have authenticated an account, the toggle will be blue and you can now share to that network.