It would definitely be open source and fully transparent in its process. Option for SMS instead of phone call is also an option. The idea of a phone call is that you can ignore a text when you're sleeping generally. It would buzz just like when you received an email.
Also, the idea of a phone call is that you can get a burner number, register that one with my app, and get it redirected to your real number without exposing that one to anyone.
It also depends on everyone's priorities, maybe someone doesn't want to be awaken by a particular app being down :) and would prefer to see it when they wake up.
OK. Ill think about it and work out a plan then.