This is a development of a previous, and very popular idea, Brilliant Idea #251. “The OnAir sign” for the home office.
This version is an app that uses GPS to notify people that you are “on-Air” and shouldn’t be disturbed.
You and the other people in or regular visits of your home that might disturb you have the app on their phones. If you go on a call, say on the phone or VoIP you press the On-Air button or if the call is on your mobile it does it automatically.
The app then figures out, using GPS whether anyone else on your notify list is near you. You can set the limit in meters. If they are, it sends their app a notification that you are On-Air (and then again that you have finished the call and are off-air).
It does that every minute that you are On-Air so for example, your partner comes home with grumpy kids whilst you’re On-Air it recognises when they (or to be precise, their phone running the app) gets near the house and sends an alert to the app.