For those throwing around the slippery slope logical fallacy about banning the radio, eating, talking, etc., it should be remembered that dealing with smart phones is distracting in that the user is required to look at the device’s screen instead of where they are going. It’s less about the driver being mentally distracted than it is about visually distracted.
Can you use your indicators without looking at them? I’d hope so! What about the radio? I can, but it depends on the specific vehicle. How about a CB? As long as it’s in easy reach. Grabbing a chocolate bar from the door pocket, opening it and eating it? Sure - it requires a little more mental concentration, but your eyes don’t need to stop looking ahead/around. Opening an app on a phone and typing a message? That’s where the difference lies… If phones had physical feedback like they used to (as people have mentioned in many other threads), it’d not be so much of an issue, but modern devices are almost exclusively visual.
Someone posting a message when the phone is on their lap (or even on their steering wheel) is going to be less aware of what’s going on ahead of them than those who simply have the phone to their ear. As others have pointed out, a one-size-fits-all law isn’t universally fair. The same goes for using a phone when stationary.
I’m not defending the law, by the way, I’m just explaining why phone use can be (but is not always, of course) more serious than some of the other activities mentioned. You’re still going to get idiots who pay no attention to their driving even when they’re not on the phone.