Nokia, the Finland-based mobile phones maker, has taken control of Symbian, a software licensing company, by buying the 31.1% held by UK-based Psion for a total of £135.7m or around 210p a share.

Psion shares plunged 30.6% to 66.5p at 10:40 GMT as the market expressed disappointment over the price. The shares have traded between 95p and 62.02p in the past year.