It's about time we cracked down on stuff like this. The evidence has been clear for ages now that it's almost equally as dangerous as just being on your phone, even if it may seem less so.
This is how people get killed. Especially cyclists who are at their most vulnerable at junctions.
Why can't people just put their phones in the glove compartment and leave the alone while in the car? Nothing is that important, and if it is then maybe consider using another method of transport that permits you to use it.
What part of “I use my phone for sat nav and Spotify” do people not get?