No matter what the phone companies are hoping for, cell phones will probably replace regular home phones in the future. Learning to trace cell phone numbers might someday come in handy for phone owners. An important reason to know how to trace back a cell number is for safety. You should know that you can not lookup cell phone numbers with a regular telephone directory. Three reasons why you might need to lookup a cell number is your kids cell phone has numbers on it you don’t know, you receive a lot of hangups on your phone or you suspect your spouse is having an affair. Infidelity is becoming more common among both men and women today. Today’s technology makes it easier for couples to cheat and have affairs. It is easy to keep an affair secret by just using a cell phone to arrange secret meetings with the spouse easily kept in the dark. If you suspect your partner or spouse is cheating all you need to do is take the unknown number and head on over to a cell phone lookup website and you will find out who they are talking to fast.