Amazon’s Prime Instant Video service is on fire in the United States — and that growth happened before Amazon even introduced its $99 Fire TV set-top box.

According to a new report from online-video delivery and caching solutions provider Qwilt, streams on Prime Instant Video have almost tripled over the past year — and in the process have passed both Apple and Hulu in terms of volume of video streaming traffic. The data was gathered from MSO broadband providers that use the Qwilt systems.

Amazon has updated its Instant Video app for iOS today, introducing support for the iPhone and iPod touch. The service has been available on iPad since August, but this is the first time it has come to smaller iOS devices, giving Amazon Prime subscribers more than 30,000 free videos in their pockets.