Actually, the device is very sophisticated, most FTers wouldn't understand how it's used.

Once the AC door is closed, and the "Turn Off Electronic Device" P.A. is made, this device is automatically set. It knows roughly what seat, and who is still on their devices. It knows who tries to hide their device under a newspaper, books, paperwork, magazines, etc. It even knows whether or not the device is in Airplane mode, or in transmitting mode....it's that Sophisticated!!!

All pax have actually seen this device. They know it so well, they know it as well as they know the "Safety Demo" speech/video!

I'm sure you didn't see the device as it walked through the F cabin and witness all the ExPs, Pls, CEOs, Keys who don't know how to follow Federal Regulations...or don't think they need to follow regulations as they don't apply to them, who were still either talking, texting, viewing, etc, on their devices.

Turn off ALL electronic devices means they are OFF. Transmit is off, device is in DARK/SLEEP mode until the PA to use them in the air is made. It amazes me how many executives who would be royally upset if they were conducting a meeting and a cell phone went off in their "Oh so important" meeting, or these same people would be upset sitting next to a someone in a theater with a phone going off, or constantly tap-tap-tapping.

That device is called a Flight Attendant who must follow a Federal Administration Regulation, or they could possibly be fined for not making sure their cabin is compliant before departure.