Read Write Web:

AdMob just released some data about how iPhone users discover new apps in the App Store and how they use them once they have downloaded them. According to AdMob, most users download apps from the App Store directly from their phones. Only 7% go through iTunes to download apps. To find new apps, 62% of all respondents searched for a specific app and 60% looked through the lists of top selling apps in the store. AdMob also found that the majority of users (62%) install between 1 and 6 new apps per month and 22% of all iPhone users download more than 11 apps per month.

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About 40% of all iPhone users use about 4 to 6 apps at least once a week. Only about 5% use more than 20 apps per week. Given how many apps most users download per month, these results validate some other reports we have seen which argue that most iPhone apps are disposable and are discarded after a few days of usage.