Have cell phones made people’s lives better or worse?

Have cell phones made people’s lives better or worse?
ladies and gentlemen, thanks for attending my lecture today.Today, i want to talk about the influence of cell phone to our life. As far as we know, the cell phone is one of the most important inventions. Because of the apperance of cell phone, we can telephone each other anywhere the signal exists. It has given a grean conveniece to our communication.You don't have to worry about you can't get the information when you are taking a walk. You also don't have to worry about you can't find someone when he is taking a walk, unless he doesn't take his cell phone with him, of course.Now the cell phone can also connect to intenet, so you can browse the news without a heavy and big computer.With the cell phone, it more efficient for us to do all things. The cell phone has changed the earth from a plant to a "town". you can talk to a guy directly even when you are at the opposite sites of the earth.
But everything has two sides, the cell phone does, too. it can send out radio when you're using it, which is harmful to you health. And it makes people keep away from each other. we don't have to face each other again with cell phones. I think most of you must have seen a movie "cell phone" which is acted by Geyou. Yes, that's an example that if you don't use your cell phone properly, you will ruin your own life.
That's all, thanks again for attending my lecture.
Thanks.