If there is no internet connection, then the app will not work, even for a single user.
If the app shows "Connecting", then the Vyzn servers may be blocked by your firewall. Ensure that the following addresses and ports are available on the network you are using to connect the HoloLens devices to the internet:
Air tap "Network & Internet":
Then, air tap on the network you want to join and follow the instructions:
You can use your iPhone to connect HoloLens to the internet. You need to enable a personal hotspot for that. Cellular charges may apply.
First, turn off the Wi-Fi and go to Settings and tap on "Personal Hotspot" to enable it:
Turn it on and remember the password:
You need Wi-Fi to be enabled on your iPhone in order for the HoloLens to connect. Tap "Turn on Wi-Fi" if you see this dialogue:
Please find instructions here: http://bit.ly/2jCSnhH.