- Press and hold should be used sparingly, such as in the case of acting as a deadman switch, emergency stop, or other compelling use case.
- Broadcast devices should display the same user feedback for UAP calls as for physical interactions. For example, if pressing the "Up" button to call a lift lights a backlight behind the button, then calling "Up" via the UAP should also light the backlight behind the "Up" button.
- Broadcast devices must attempt to implement all available physical actions via the UAP, giving UAP functional equivalence. If the device has an interaction unsupported by UAP, please submit an interactivity request to be considered for inclusion in the protocol.