The grandaddy of all smartphones: Nokia's Communicator 9000 turns 25

Nokia's Communicator flip phone went on sale in August 1996 and was equipped with a fax function, calendar and calculator, ushering in the golden era of smartphones. – dpa

"The office in your back pocket." That was Nokia's promise 25 years ago when it launched a mobile phone that could pass as the forefather of today's smartphone.

But compared to the phones today, you needed a generous back pocket: The Nokia 9000 Communicator was almost 4 centimetres thick and weighed just under 400 grams.