As it currently stands, in order for accessories like the Pebble smart watch and apps like Light Flow to utilize your Android devices notifications, there needs to be a little tinkering done. With Android 4.3, that looks to be changing in a big way.
According to a recent tear down of a leaked Android 4.3 ROM, Google is going to allow developers to, as Ron Amadeo of Android Police puts it, replicate the notification panel. In laymans terms, devices like smart watches will be able to act as your notification panel, complete with notification actions and all. This is huge news for accessory makers, and it opens the door to a world of possibility. It shows that Google not only cares about accessory developers, but that it may have ideas of its own coming in the near future.
As far as how this changes things for apps like Light Flow, things are just going to be easier to implement. No more hacks or workarounds will be necessary to take full advantage of notifications. This may, in turn, lead to more experimentation and faster updates for already existing apps. But dont expect anything too drastic to occur in this area.
Another interesting aspect of the changes to the notification panel are what this means for replacement notification bars. While all the necessary parts arent present quite yet, this may very well be the first step in Google allowing Android users to download and select their own notification panel from Google Play. With the stock Android keyboard already available, all youd need is an official stock launcher and notification app to get the stock Android experience on any phone.