Developers looking to attack mobile app segments where they might have the best chance of scoring big with smartphone users would be well served to take notice of Nielsen’s latest findings. The market research firm on Wednesday published some findings from its Mobile Insights and Mobile Apps Playbook reports for the second quarter of 2011, and “Games” was once again the most popular app category. In the second quarter, 64% of app downloaders — smartphone users surveyed who had downloaded an app within the past 30 days — reported having downloaded at least one game over the past 30 days, just ahead of weather apps at 60% and social networking apps at 56%. What’s more, a whopping 93% of app downloaders are willing to pay for the games they play. IPhone owners seem to be the most avid gamers according to Nielsen’s data; iPhone gamers play games for about 14.7 hours on average each month, nearly twice as long as the average mobile gamer last quarter. Nielsen also found that consumers with iPhones, Windows Phones or Android phones were likely to have downloaded the games they play, while BlackBerry users and feature phone users typically played pre-loaded games. Hit the break for additional charts highlighting Nielsen’s findings.