Most popular free iPhone apps

POSTED: 7:24 PM PDT June 24, 2012    UPDATED: 9:41 AM PDT August 15, 2012 
Pinterest iPad app screenshot

Social-bookmarking service Pinterest launched its popular free iPhone app last year and recently announced that it is now being offered to Android devices and iPads. Here's a look at the most popular free iPhone apps of all time based on number of downloads.