I think you really want to be looking at sowatch as a basis for that sort of thing, Rockwatch is very much specifically targeted just towards the Pebble, and as such is written in python so that it can make use of libpebble. Whereas I believe sowatch is designed to be more general. However each device is still going to need its own back end implementation within sowatch to handle its specific protocol for notifications, firmware, etc. That sort of thing isn't standardised across device manufacturers.