A female voice guides you at every step. Too bad we can not adjust the volume dailleurs.
When night falls, the ring turns green to tell you that everything is fine and if you spend the night near the detector, it illuminates the ring of a soft white light. You will find dailleurs in the settings app a brightness setting of the pilot mode, but do not expect that it illuminates a room!
In short, it's a pretty high-end multifunction sensor connected.