text: A second reason to not use while driving is that it reduces your brain activity while driving. So even if you are using your phone and paying attention to the road your brain still doesn't work as well while driving. The brain isn't meant for multitasking and texting or holding your phone and talking to someone is a lot of work for your brain. So it slows down the brain activity you are using towards driving and puts it more towards you using your mobile device. This will reduce your reaction time and your full judgement. These are just some of the reasons why you shouldn't use your phone while driving.