Once plugged in, the tool offers the basic 'Anniversary Update' to the IDOL 4 Pro, i.e. Redstone. i.e. the out of the box state. From which the Creators Update can be applied as a production update (of which more shortly) or you can go right up to the latest feature2 branch using Fast ring Insiders status.
As the changelog above shows, in addition to IDOL 4 Pro support, there's also support for a couple of new Windows 10 phone-like terminals, pictured below. They're not consumer phones but it's interesting to get a little peek into the world of enterprise, with devices that you're only ever likely to see if they turn up at your door when you sign for a package (e.g.)