First, NYC Digital's website should become a one stop for social media / developer / civic data apps (see http://digital.cityofchicago.org )
Second, NYC notify should become a 360° notify program that is fully integrated into public space.
+ Bus shelters
+ Deploy a feed that can be incorporated into elevators, + POS cash registers, and other public information screens.
+ An public API that can be integrated into mobile web and web enabled set top / internet TVs Make all city services more accessible via these methods
+ systems for vision impaired New Yorkers
+ Include Schools SMS / Mobile notification system ( https://a858-nycnotify.nyc.gov/notifynyc/ )
+ location based targeting of NYC notify