Using WebPageTest

Chapter 6. Mobile Testing

Generally speaking, traditional web developers have always had to ensure that their code worked across popular browsers. This has become the universal truth of web development; users can and will access the web however they are able. In recent years, the freedom of accessibility has become less about “taking back the Web” by choice of browser and more about convenience of access with mobile devices. And it hasn’t stopped at mobile phones, either. People will access the web on their tablets and watches, and they will even get it projected onto their eyeball if they so desire. While we’re still waiting for the wearable WebPageTest agent, there is already support for tablets and phones.

In this chapter, we will explore the options that WebPageTest provides for mobile web performance testing. Mobile support falls under two categories: emulation and native. Rather than testing on an actual phone or tablet, emulation runs on desktop browsers configured to act like a mobile device. For the real thing, WebPageTest agents can actually control physical mobile devices. As we’ll discuss, each tool has its drawbacks and advantages.

Desktop Emulation

It is common for web developers to call their site “mobile-friendly” if it is responsive. One way to do this is to give mobile devices the entire desktop page and rely on client-side code to force it to be mobile-friendly. For example, a page could be viewed on a large desktop monitor or a small phone screen, and some ...