From the comScore Blog:
Yes, there probably is an app for just about any task a smartphone user hopes to complete, but our recent U.S. Mobile App Report shows that a staggering 42 percent of all app time spent on smartphones occurs on the individual’s single most used app. And nearly three out of every four minutes of app usage occurs on one of the individual’s top four apps.
That said, more than a third of all U.S. smartphone owners download at least one app per month, and the average smartphone user within this segment downloads three apps per month.
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