Once upon a time in New York, the police could only issue a ticket for using a cell phone while driving if the motorist also committed some additional, different violation of the Vehicle & Traffic Law. A cop could always pull you over if he saw you chatting on your cell phone, but if you were not otherwise breaking the law, the worst the officer could do was give you a warning and send you on your way.
That all changed this summer. The Legislature amended the VTL to upgrade "Use of a mobile telephone" while driving to a primary offense, meaning that an officer may issue a ticket for using a cell phone while driving even if he observes no other violation of the VTL. (See N.Y. Veh. & Traffic Law 1225-c.) The revisions were effective July 12, 2011.
Simply "holding a mobile telephone to, or in the immediate proximity of, the user's ear" is considered "using" a cell phone for the purposes of the law. (See Veh. & Traf. 1225-c[c].) A driver holding a cell phone "to, or in the immediate proximity of his or her ear while such vehicle is in motion" is presumed to be "engaging in a call" for purposes of the law. (See Veh. & Traf. 1225-c[b].) This eliminates the popular "you can't prove I was making a call" defense. The section does not apply if the motorist is using the cell phone for certain emergency calls, or to police officers using a cell phone "in the performance of their official duties." (See Veh. & Traf. 1225-c.)
The maximum fine for a cell phone ticket is $100, and a violation adds 2 points to the driver's DMV record. (See here for the full table of points for specific traffic violations.)