A long, long time ago, cell phones were used for just one thing: making phone calls. They were bigger than a book (a bound book), heavier than a brick, and used primarily for emergencies.
Forty years later, cell phones are so much more. No longer novelties, they are an integral part of our lives and hold a world's worth of information.
Take a look back at the evolution of the cell phone over the years.
Here, Chris Brasher, co-founder of the London Marathon, talks on a cell phone during the 1985 foot race.