There’s some devices that look to be for a pilot on the silver line. If you step onto the bus at the back door, there’s a device attached to the right hand yellow pole. It’s about the size of an iPad mini I’d say? If you’d be able to fit onto the bus while boarding at the rear door, you’d be able to reach the very small tap device no problem. If you can’t reach it, there’s probably not room for you to be getting on, moot point.