One of the advantages of running Windows 10 on the HoloLens is that it has all the regular features that you would expect. From a developers perspective, one of those being the Device Portal which is awesome. It is essentially a web server that is being hosted on the machine, and allows you to manage your device over Wifi and USB.
It is a must have if you want to stream your apps (including Holograms) so that others can see it, or alternatively you can record and then share. And of course there are details for various debug situations and the Virtual input saves your fingers from getting tired! 
You also use this to side load the apps you built. There are REST APIs you could use if you want to program, and there is also a UAP app on the store (more on that in part 2).
To get to this, you browse to the IP address. Below are a few screenshots from my playing around which shows you the various aspects of the portal and what all you can do. And the beauty of this is, as a Windows developer, this all should be very familiar and nothing new.
Home Screen – once you login
3D View Settings
Mixed reality capture – one of the key elements that lets you share the magic with others
Perf Tracing and the various levels you can set as part of Windows Performance Toolkit. This is WPR/WPA support in Systems.Diagnostics.Tracing – see this post for more details.
Process details and you can sort by the relevant column.
Process details #1 – showing various details from Power to Framerate to IO, Memory, etc..
Process details #2
Process details #3
App Manager which is where you side-load apps and manage them
Crash Data – the name says it all
Kiosk Mode – this is really interesting; you can ‘lock’ into one app and use that. I wonder how one breaks out of it when done being in this mode and wanting to get back to ‘regular’.
All the ETW (Event tracing for Windows) details and the providers you can want. Again pretty standard stuff.
Simulation – not sure if this is used for regression or playback in another setting – where the room capture would help. Does open up interesting possibilities. I think it might allow one to capture the spatial mapping of a room, which then you might be able to use in the emulator (such as someone has done here).
Networking Configuration where you go and manage this.
Virtual Input – a great time saver.
And finally some of the security settings to ensure no one on the same subnet is mucking with you; or when there is more than one device then you talking to the right one.
