You will need an active license on any device that is running check-in. If an iPad/tablet is running check-in, it will need to be licensed, as will a computer that is running check-in. Alternatively, if you have a iPad/tablet that is running check-in and is using a computer only for the sake of printing, the iPad/tablet will need to be licensed, but the computer will not (since only the tablet is actually running check-in).