Crisis averted!
While the US-page shows this:
The Japanese site shows this:
which translates to "Headphone and Mic-Jack - You can connect headphones, a microphone or headphones with integrated microphone"
So Switch can use regular headsets, which are very likely to be used for voice-chat, etc.
Ta-da.
Whatever the App can do, it will be available on the Switch itself in some form. Nintendo just spent a lot of time unifying their online service, they aren't going to split it up again.
My guess; Nintendo knows we are on our phones all the time, and if they want people to use their games socially on-the-go, they can't rely on hoping people will adopt Switch as their primary communication (ie for organising online parties etc). It just won't happen. So they need a gateway app on our phones to get us to turn on Switch.
I see their thinking like this:
- I'm on my phone as always
- I get an app notification to play some Switch
- Can enter chat/organise party from my phone (over 4G or whatever) whilst I find some WiFi
- Find Wi-Fi, Boot up the switch, play online and continue party/chat via Switch.
Of course, if you're sat at home, just do the first 3x steps on your Switch.
That's my theory. Only way this all makes any sense.