The world’s number one mobile phone maker Nokia has cut its profit forecast for the second half of this year and lowered its prediction for market share.Nokia is facing tough competition from the likes of Apple, Samsung and Blackberry maker Research in Motion. It scaled back its second-half underlying operating profit margin forecast to same level as in the first half of the year. Nokia also said it will maintain market share this year, not increase it as previously forecast. The handset industry is facing its worst downturn ever and Sony Ericsson – which is the fifth largest manufacturer – has just reported a deep loss for the period from April to June with sales down 40 percent. The pretax loss of 283 million euros was much as expected and an improvement on the 358 million euros loss of the previous three months.