InMobi, the largest independent mobile advertising network, on Friday announced its “Mobile Insights Report: North American Edition” for the month of January, reports AppleInsider. Thanks to the launch of the iPhone 4S, Apple’s iOS mobile platform surged 12 points to surpass Google’s Android operating system in North American ad impressions. Apple’s share of 23.2% in October of 2011 increased to 35.3% in January, with Android losing 3.2% in the same time frame for a 32.7% share in January. Research in Motion’s BlackBerry mobile platform dropped 8.9% from October to January to an 11.6% share. “The iOS growth we are seeing may be attributed to the tremendous success of iPhone 4S and iPad in the ecosystem,” said Anne Frisbie, vice president and managing director for InMobi’s North American operations. “Overall, we are excited to see InMobiâ€™s available impressions exceed 55 billion in North America, and look forward to continuing our rapid growth through 2012.” The data comes from InMobi’s advertising network, which serves more than 93.4 billion ad impressions around the world each month.