Part of the problem is the user - to make someone preger using the electronic thing over to the traditional blackboard you have to make it easy to use.
Requiring your phone to connect to a specific WiFi network (that of the scoreboard), then entering an IP address for URL (a captive portal would make this part easier) is not the best in user friendliness. Though it's admittedly less bad than expecting them to install an app just to play a game of darts with you.