Even as Apple's share of the smartphone market declined in the fourth quarter of 2013, the rise of smartphones to replace more basic feature phones has allowed the company to continue increasing its share of the overall mobile phone market, according to new numbers from research firm IDC. According to IDC, yearly smartphone shipments topped one billion for the first time in 2013 and now represent 55 percent of mobile phone shipments, up from under 42 percent in 2012. The fourth quarter alone saw smartphone capture over 58 percent of the overall mobile phone market. Worldwide smartphone shipments in 4Q13 in millions of units (Source: IDC) For full-year 2013, Apple's iPhone sales increased by 12.9 percent over 20
