Even though the iPhone has been available in the UK for more than two years now, Vodafone's recent launch of the device on its own tariffs has shown just how enduring the popularity of Apple's mobile is, with 100,000 customers picking it up in the first seven days of its availability on the network.

50 per cent of this total includes pre-orders for the phone, although this was matched by sales in the first week and with a pay as you go version on the way it is likely to continue to be one of the strongest performers in Vodafone's portfolio.

Vodafone's Peter Kelly said that the network would be promoting the iPhone heavily as a business phone in order to present it as a real alternative to the BlackBerry range.

Guy Laurence, who heads up Vodafone's UK operations, added: "The demand from both consumer and business customers has been phenomenal. They want an outstanding phone on an outstanding network and we're delivering that."

Considering that the iPhone 4G is arriving in mid-2010 and the Google Nexus One is just around the corner, the smartphone market seems set for ever fiercer competition this year.