Earlier this month, we reported on stats from Nielsen indicating that between them, Apple’s iOS and Google’s Android account for 64% of US smartphone owners. However, the company has just released new research showing that these platforms over-index for actual app usage – between them, they account for 74% of US app downloaders. What’s more, having surveyed people who had downloaded at least one app in the last month, Nielsen found that iPhone owners have an average of 48 apps installed on their devices, while Android owners have 35. People with Palm webOS handsets have 21, Windows Mobile owners have 17, and BlackBerry owners bring up the rear with a mere 15 apps on their phones. To hammer this comparison home, Nielsen also says that 68% of iPhone owners use apps multiple times a day, versus 60% of Android users. BlackBerry? 29%.