Well that is an easy question to answer....
"Wonder how many train, cruise line, and bus passengers would appreciate and welcome these devices."
This is not a new device at this point, it has been in development for sometime, announced well over a year ago at least. And it has been in actual production since at least last October, right?
So surely EDIG has had the time to market the player to the areas you mention above by now, and the players are available for order. So just count up all the orders EDIG has received from those various areas for you answer. According to the last SEC report, I count exactly ZERO.