"...listening out for loud and repetitive noises like fire alarms, and vibrates to wake you up when it hears anything similar"
Would that include dog barking? And do you plan to offer it for iPad/Android at any stage?
My only salvation these days is to save articles to Pocket (or Readable, Instapaper, etc.) on the iPad and go to the local coffee shop for a session of concentrated reading. (It's a village, there's no wifi.)
I take notes on paper and action them when I'm back on the internet.
[An unintended bonus is that my handwriting is starting to get back to its pre 24/7 internet level, i.e. legible and quite pretty rather than the scrawl of someone who's more comfortable with a keyboard and mouse.]