ELECTRONIC organiser company Psion added more than £100m to its value as shares rocketed on the news of deals with telecom companies Nokia and Ericsson.

Shares in Psion, which has its industrial manufacturing base at Milton Park, near Abingdon, closed at 423.5p - up 142p on the day, a rise of more than 50 per cent.

The joint venture company Symbian, 40 per cent owned by Psion, aims to develop the company's EPOC software system into a global standard.

David Potter, chairman of Psion and chairman of the joint venture, said: "The worlds of mobile computers and mobile communications are converging and this transaction positions Symbian at the forefront."

The three companies are banking on a dramatic expansion in mobile communications, combining mobile phones with palm-top sized computers and organisers.

The world mobile phone market is expected to grow from 200 million subscribers in 1997 to 600 million by 2002.

Psion estimates that about 90 million of these subscribers will use so-called smartphones combining a standard mobile phone with an electronic organiser.

Symbian aims to make Psion's software the standard for these systems.

Psion will be the senior partner in the business with its 40 per cent stake while Finnish Nokia and Swedish Ericsson will take 30 per cent each.

The two Scandinavian companies are paying £57.5m into the venture. Symbian itself may seek a separate listing on the US NASDAQ exchange.

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