Seems like it could be done as a phone app? Anyway, departure times are only part of the problem. I often want to know the arrival time of a train that has already departed, because I have to pick up a passenger who is aboard an incoming train. Or in the case of buses (nextbus.com in the US), I'm already on board bus #123 and I want to know its current location as a position on the bus route, so I can estimate how long til I reach my desired stop. This is for cases when the bus is going through an unfamiliar part of a city. The data is already on the servers, so it's annoying that the apps don't use it.
"Seems those scissors could be a knife instead? And anyway, cutting paper is only part of the problem, sometimes I want to cut steak as well. Or sometimes I want to carve something from wooden blank"
No, this could not be done as a phone app. This is a narrow-scope product with specific goal: let someone know when to depart without having to stare at the phone continuously.
Nothing stops you from running the app nonstop and mounting the phone on the wall. In Android, this is called Kiosk mode. It prevents any other apps from running on the phone.
Have you seen the size of that thing? that's 48x18cm, or 20" diagonal. That's not even close to the phones.
And yes, thing thing _could_ have been implemented as a embedded large-format Android tablet with the kiosk mode app, installed in a wall-mount case. This would likely be more expensive to produce, and would look worse.
In other words yes, you can cut paper with knife.