Thanks to the News-Sentinel staff for this overview of the new law coming July 1.

New cell phone laws at a glance
The countdown to New Year’s came and went this week, and now a new clock is ticking: In six months, it will become illegal to drive while holding a cell phone to the ear.
In other words, you have until July 1 to buy a hands-free device, or buy a whole new phone if it doesn’t work with such devices. Teenagers cannot use any communication device, even with hands-free devices.
The July 1 date has been widely publicized since the law was passed a year ago, but law enforcement officials say they are still being deluged by calls from people who think the law started this week. Some thought it started in July 2007, and some even thought it went into effect a year ago.
The bottom line is that, after July 1, if a cop sees you holding a cell phone while driving, you can be ticketed. You must use a hands-free device so that you do not have to hold the phone while driving.
Most phones have a place to plug in an earpiece, and many now use Bluetooth technology, which does not require wires. Headphones won’t work, as California law does not allow drivers to use headphones on both ears.
But teenagers don’t need to bother investing in hands-free equipment — on July 1 it will become illegal for those under age 18 to use any kind of communication device while driving.
The only exception to both laws is during an emergency.
The base fine for each offense starts at $20, which doesn’t sound too steep, but that doesn’t count various state and court fees. Once they are tacked on, the total fine will be well over $50. For subsequent violations, the fine will more than double.
— News-Sentinel staff.