Allow a way for people to get your attention with the companion app
It's hard for family members that have something urgent to tell you to get your attention while you're in VR, especially with full headphone/earphone on. One of the way i can think of is to let people talk to the phone's microphone, and feed the audio to the headset. To put things into perspective, my wife told me trying to get my attention when i'm playing beat saber is like reaching her hand into moving fan.
When introducing VR to friends, i would like them to have full immersive experience, that means using earphone for full audio immersion instead of the built in speaker. Down side of that is, there will be bunch of "HUH? WHAT DID YOU SAID??" when i'm trying to instruct/guide them. Using the companion app to speak to them would be nice in this kind of instance.