The obvious one would be a dedicated device that just observes the world around you (sound, video, etc) and provides some kind of ambient intelligence to suppor

The obvious one would be a dedicated device that just observes the world around you (sound, video, etc) and provides some kind of ambient intelligence to support your day in context. This cannot be done on a smartphone and none of the other devices move around with you. The big question is whether there is a killer use case for something like this.