Once opened, the app instantly begins giving users a reading of their internet speed. Once the test is fully complete, results can be checked against results from SpeedTest.net, another popular internet speed checking solution. Both the website and app utilize simple, minimalist designs, with the service's logo and download speed tracker taking up much of the space. The refresh button, the lone button in the app, allows users to restart the test.
On its blog, Netflix's Sergey Fedorov and Ellen Livengood explained that FAST only displays download speeds because thats how most users interact with the internet, whether it be streaming video or loading webpages.
To test speed, the app and website undergoes several download tests using Netflix's technology and services, including downloading chunks of a 25 MB video file through "a variable number of parallel connections." Fedorov and Livengood go into technical detail about how the service works on the company's tech blog.
FAST Speed Test is available in the App Store for free [Direct Link]