Back in August, we did a 4-day promotion of 360 Panorama where we cut the price from $0.99 to Free. The limited time offer was also promoted by Apple’s App Store Twitter (@AppStore) and Facebook accounts, and got picked up around the web.
Prior to the promotion, all we had heard about free app promos was the rule of thumb that you should expect “5 to 10x” the downloads. We didn’t really know what to expect in regards to user engagement or App Store rankings. So, we decided it would be fun to collect the stats on what happened and see: What happens when a best selling iphone app goes free?