The cellular phone has been around since the 60s and 70s. When they first came out only business people, military, and those with money were able to afford to have one. I remember as a kid growing up in the 80s watching tv shows and the characters would have car phones. Cell phones became more mainstream as well as smaller in the late 90s it wasn't unsual to go to the mall and see people with a cell phone. Now a days you can't hardly pass someone on the street without them using a cell phone. The price and services provided has come down and now everyone can afford to have one.
The cell phone brings back the sense of staying connected. For decades people have kept in touch with each other using letters and phones. With mainstreaming of cell phones and web enabled phones this has become easier to do.