Good idea for new service. But i don't pay for such a service as services will auto restart when it fails. When server getting down, i can always reboot myself with out waiting for some one else do it.
I applaud your effort and idea, however this is a feature that many providers already offer in some way. I do not believe there will be enough demand to make this a worth-while venture. This entire industry relies on connection to the internet in some fashion, so while a phone may be preferred by a few, the vast majority will completely ignore this concept and favor doing it through the web.
Regardless of what you choose to do, the best of luck to you!