1. For a Linux user, you can already build such a system yourself quite trivially by writing a shell script, compiling your own custom X server, and then monitoring the screen state for full-screen apps. For Windows or Mac, you just remote desktop to your Linux box with built-in software.
2. It doesn't actually reroute the notifications. Most people I know want to be able to perform presentations without the visual clutter of notifications, but they still carry a phone to check their Instagram while presenting. This does not solve their notification issue.
3. It does not seem very "viral" or income-generating. I know this is premature at this point, but without charging users for the service, is it reasonable to expect to make money off of this?
In reality, this is a great landing page and a cool idea for an app. Also, I have nothing but respect for people who share their honest, thoughtful assessments on HN. The future is tough to predict.
> It does not seem very "viral" or income-generating. I know this is premature at this point, but without charging users for the service, is it reasonable to expect to make money off of this?
Does everything have to be a moneymaker? Like you said, this would be trivial to setup yourself. It's a nice piece of software that provides some advertising for his other products.