Sửa lỗi ngữ pháp đoạn văn dưới đây

Cell phone, it is the one of the most important things in my life. It keep me in touch with my family and friends. I can play game, listen to music, read news, take a picture when I have it in my hands. I can say that my life would be boring and slow if I hadn't it. Beside a ot of advantages. It make us waste time, effects health and losing focus.