You can use an Amazon Fire TV Stick for the "Showcase TV" function in myJACK.
You have to buy the stick and then load the "meinereisedatenTV" app onto the stick. You can also do this via Amazon.
Please note that the Fire TV Stick requires a standby deactivation if you want to use the television for a longer period of time (e.g. at night) to display your offers.
Which TV sticks make this function available, please discuss directly with the seller.