Pictures: Smartphones celebrate 20th birthday

16 August 2014 Last updated at 08:54 BST

The IBM Simon Personal Communicator went on sale 20 years ago, on 16 August 1994. It is considered to be the first smartphone.
A museum employee holds up the IBM Simon, the first smartphone to go on sale 20 years ago
Meet Simon - the grandfather of the smartphone! The IBM Simon Personal Communicator went on sale 20 years ago, on 16 August 1994. It is considered to be the first smartphone.
A museum employee holds up the IBM Simon, the first smartphone to go on sale 20 years ago
Simon was pretty basic by today's standards. It had a cartridge slot for installing apps, a black and white screen, and it didn't have an internet connection so you had to connect it to a computer to download your messages.
Nokia 7110
The Nokia 7110 is considered the first media phone with a mobile 'WAP' browser, an early form of mobile internet. It was very slow and could only display text and basic graphics - a far cry from the full internet access we enjoy on phones today.
Sharp J-SH04 mobile phone
The Sharp J-SH04 mobile phone from Japan was one of the first mobile phones to have a built-in digital camera. Modern smartphones take crisp 8-megapixel photos but the J-SH04 phone could manage just 0.3-megapixels. It was on sale in the year 2000.
Blackberry 5810
By 2002 smartphones were starting to look a little more familiar. The BlackBerry 5810 was the first that could make phone calls, send email and access the web. It even had some basic apps like a music player.
The IBM Simon next to a modern smartphone
Modern smartphones are much smaller, slimmer and faster than the IBM Simon. Some people complain that their phone battery doesn't last all day, but they should count themselves lucky. The battery in the IBM Simon could only last one hour making calls! A collection of smartphones from history are on display at the Science Museum in London.