drum118
Superstar
I made that that comment years ago when Onestop started the program.The screen can simply be projected onto the wall across from the tracks, as many cities do, ads and all.
You can have a number of these wall panels along the full length of the platform that are way lager and easier to read than the current 1-2 overhead ones. Also on the centre columns in various stations.
It was pointed out by others, its only pennies per rider to have these screens than going to the outside market to supply them with adds on them.