DriveMob and Box X are two very different things. DriveMob is and IPTV service that can be paid for by the month or by the year and give you access to over 3000 live channels. It can be logged on and used on 3 boxes simultaneously.
Box X
The $3.97 fee is monthly for the App called Box X that runs the Entire box. It will work on 4 boxes or devices for that price of $3.97 total. It updates the box on all the Apps on your box on a monthly basis and includes help and support. Box X has a lot of cool new benefits. Here is the Demo video to show you All thats possible!:
https://www.youtube.com/watch?v=bNhz8TwPfEc&t