Another update that the team surprised me with:
https://www.youtube.com/watch?v=tSRjoU_9A9gOne of the challenges that we face is how to show a platform and protocol when the output is invisible beams of light being sent between devices when there is no internet and no connectivity (and is why we are investing time and money building apps that we will release as Open Source projects). I thought this video showed this off pretty well.
This demo is on the right track. Probably not that impressive to anyone else who defaults to "cool story bro. I also have 4g" mindset

Maybe in person start the demo by having people volunteer to preload the app and remove their SIM's from their phones first.