Made by IBM, the 'SIMON' had a touchscreen and a stylus, as well as basic apps.
Charlotte Connolly from the Science Museum in London says it had some drawbacks.
“It was the first device to bring together a pocket computer and a cellular phone” she said.
“It was really expensive at the time – it was 899 dollars – (and) the battery life on this only lasted for an hour”.
“Unfortunately, it didn't quite sell as well as they'd hoped” she added.
