Netflix speed tool can tell if your stream will be crappy

Wondering how fast your internet performance is on your smartphone or tablet? Netflix has launched a mobile speed test app to answer that question.

Rolled out on Tuesday for both Apple iOS and Android users, Netflix's Fast Speed Test estimates your present internet download speed. To determine your speed, the app runs a series of downloads from Netflix's servers and then displays the overall result.

As it's designed by Netflix, the real aim of Fast Speed Test is to make sure your Netflix connection is fast enough so your content is streaming smoothly. A slow connection can decrease the quality of your video or even disrupt your online viewing altogether.

People increasingly use their phones and tablets to listen to streaming music, watch TV shows and movies and perform other bandwidth-intensive tasks. So obtaining a fast internet speed on a mobile device has become more critical.

Fast Speed Test is designed with a simple, minimalist approach. As soon as you launch the app, it runs its test and then shows you your internet speed. You can refresh the app to run another test. You can also scroll down the screen to read an FAQ with information on the app.

If your mobile speed is consistently slow at home, it may indicate trouble with your modem, router or other equipment. It could also point to a problem with your internet service provider.

The Fast Speed Test has its origins in Fast.com, a website launched by Netflix this past May to measure the internet speed on your computer and other devices. In a blog posted Tuesday, the company explained in technical detail how its speed testing works. Netflix declined to provide more information beyond its blog post.

Netflix generated controversy in March when it admitted it had been slowing down video speeds for AT&T and Verizon subscribers. The company said it started the practice to "protect consumers from exceeding mobile data caps."