Mobile phone retailer and broadband provider Carphone Warehouse has upped its full year guidance after posting better than expected half year figures.Headline earnings per shares (EPS) almost doubled to 6.0p in the six month ended 30 September compared with 3.2p previously.The group increased its headline EPS guidance for March 2010 to between 14.0p and 15.0p (full year 2009: 12.6p) due to the strong EBIT performance in both TalkTalk Group and Best Buy EuropeAt TalkTalk broadband division, which it plans to spin off, customer growth is ahead of expectations. Excluding Tiscali, the lowly-rated Internet service provider (ISP) it bought for £236m, Carphone added 124,000 net new customers in the first half, and expects continued strong customer growth in the second half. Hadline pre-tax profit rose to £75m compared with £40m last time, while revenue was up 13% to £789m. The board has declared an interim dividend of 1.45p per share (2008: 1.35p per share). 'Both TalkTalk Group and Best Buy Europe have traded well in the first half of the financial year. Each business has delivered a significant year-on-year improvement in operating free cash flow, with Headline EPS at the top end of market expectations. As a result, we are raising guidance for the full year to March 2010,' said chief executive Charles Dunstone.Shares in Carphone Warehouse have more or less doubled since the start of the year as the mobile phone retailer and broadband provider has ridden the wave of the phenomenally popular Apple iPhone.