A:Answer Hi James, there is no difference in the smarts between the Nest Mini and the Nest Audio. They can do the same things, including broadcast. The only difference is the size and sound quality.
If you are looking for great sound, get the Nest Audio. If you are looking for decent quality sound in every room, get the Nest Mini. Also, note that the Nest Mini frequently goes on sale for $30.
Hope this helps!