Install the player the email names
On an iPhone or iPad, use the App Store. On Android, use Google Play. Install the player named in the welcome email, then enter the same username, password, and server address you used on the television.
The phone does not need its own subscription. It uses one of the screens on your plan. If the living-room television is already playing and you are on Moon Start, the phone will be refused until the television stops. Moon Plus allows three screens at once, Moon Max five. See which plan fits.
Picture and data
On mobile data, prefer HD over 4K. A football match uses a lot of data. Wi-Fi at home is the steadier choice. If the phone plays and the television does not, the account is fine and the television’s network is the part to fix. That case is covered in buffering.