A world without phone numbers. That may sound ridiculous, but I think we’re actually a lot closer to it than you may think. Now that so many of us have smartphones and tablets we're using them to communicate with our friends over the internet instead of calling or texting.
As recently as a few years ago most of our phone communications were through phone networks (calls and text messages). Now, more and more communication is done through the internet: Apple's FaceTime and iMessage, Google Hangouts, Facebook, WhatsApp, Skype, SnapChat, etc. When we use these services we're not dialing a phone number, we're connecting with a friend's email address or username. If someone wanted to they could easily get rid of their phone number and use these apps to communicate with friends. Most teens probably wouldn't miss a beat without a phone number. Personally, I use free apps to call and message over the internet so I don't have to pay for voice and texting plans.
Apple's iPhone, the most popular phone in America, comes with free apps for audio and video calling and messaging that don't require a phone number or phone service (but they only allow you to contact other iPhone, iPad, or Mac users). In the US, smartphone penetration among mobile phone users is somewhere around 70% depending on the study you look at. Just about everyone I regularly call or text has a smartphone or tablet. Even my technophobe mother is finally online and addicted to her iPad. Ever since she got her iPad we don't call each other anymore, we FaceTime and iMessage. As smartphone penetration continues to grow, especially among younger people, I think phone numbers will become less important and relevant. If a few of these services become popular enough that the majority of smartphone users have them we can stop exchanging phone numbers and instead exchange usernames. Isn't it easier to remember someone's username than a random string of 10 numbers?
Companies like Apple, Google, Facebook, and Microsoft recognize this. I believe it's why Facebook acquired WhatsApp for $19 billion and why Google is in the process of consolidating its messaging and video conferencing services under Hangouts. It's also why all of the major wireless companies have moved to bundle unlimited calling and texting with their cell plans.