The Benefits and uses of an Address Book Address Books in the Days of Technology. These days remembering someone's address or phone number seems to have gone down the way of black and white TVs. A cell phone address book seems handy and easy to access yet no one seems to realize that in the case of a lengthened power outage or emergency cell phones still need to be charged. Having all your addresses listed in a book that is always on hand and does not need to be charged or replaced every so often can be a life saver on days where your cell phone or computer crashes or has no charge left. An old fashioned address book needs little maintenance and no power. It is self-contained and always on hand when needed.