The GigaOM website estimates that people with cell-service contracts replace their phones every 18 to 24 months, but manually entering your contacts with each upgrade is both tedious and time-consuming. If you've synchronized your smartphone and other devices to an account such as Microsoft Exchange Server, you can relax: Your contacts will migrate to your new phone when you connect. Another option, if both phones have the right hardware, is to use the SIM card holding your old phone's data to transfer your contacts. Some phone vendors also offer transfer software, such as Verizon's Backup Assistant app, but even if none of these methods applies to your situation, you still have alternatives to typing in every single name and number.