What improvments were made to the origanal telephone?

I'm nearly 59 years of age so I might be a lot older than you are, that being said, the first telephone that I remember seeing was the crank type telephon. You had to crank it several times to reach the operator and give the operator the number you wanted to call. It wasn't long after that, that the rotary phone came into existance. Then the touch tone phone arrived. Now look at us today. Cell Phones in nearly everyone's hands from young kids, to old men like me. Actually I have two cell phones, one for business and one for personal use. People driving to work, talking on their cell phones perhaps to a fellow worker, to a husband or wife or whoever. Times have changed a lot, and telephones too.