The Notifications Summit was recorded live October 1, 2015 @ betaworks in New York. Gathered were a group of technologists, developers, and thought leaders.
Programming notifications as the third instance:
A conversation w/ Linden Tibbets (IFTTT), John Milinovich (URX) and Josh Elman (Facebook, Twitter, Greylock)

What are the limits of functionality within the notification layer? Where will platform makers draw the line? Can they draw a line? App makers have an interest in pushing out as many notifications as they can get away with in order to capture as much engagement as possible. Given the tragedy of the commons (i.e. our attention) this noise creates, how do platform makers (i.e. Apple and Google), app makers, and users navigate these different goals?