Works a bloody treat… You need to install the TestFlight app on Apple TV an then on the Iphone or ipad where you have express VPN installed, navigate to expressvpn beta site and join ‘google that’. join the beta, follow the instructions and when you install the beta app on iphone go back to test flight app in apple tv, download the express vpn app sign in and away you go… took me 5 mins start to finish and works a treat