A webpage appears to hang for several seconds before anything appears on screen. Which of the following steps is likely to help reduce load times?

A webpage appears to hang for several seconds before anything appears on screen. Which of the following steps is likely to help reduce load times?

Answer

•  Place image and script files close together in the HTML.
•  Elimate any use of JavaScript to "lazy load" files.
•  Disable Chrome Developer Tools, as the software can create slowdown in the critical rendering path.
•  Set inessential script files to load after the page body.

What kinds of images are resolution- and scale-independent?

What kinds of images are resolution- and scale-independent?

Answer

•  Vector images
•  Raster images
•  Large images
•  JPG images

A webpage with several menu animations performs poorly, even on the latest mobile phone. Which of the following is a likely cause of the slowdown?

A webpage with several menu animations performs poorly, even on the latest mobile phone. Which of the following is a likely cause of the slowdown?

Answer

•  The animations force the browser to recalculate (or reflow) layout.
•  The menu occupies a percentage, rather than fixed width, of the screen.
•  Several CSS font styles have been applied to the menu text.
•  Menu animations that are fluid in portrait mode slow down in landscape mode.

What tool can you use to measure mobile website performance on a desktop computer?

What tool can you use to measure mobile website performance on a desktop computer?

Answer

•  Android emulator
•  Speed Index
•  Scalable vector graphics
•  Chrome Developer Tools

How does the application (app) shell of a Progressive Web App (PWA) improve performance in poor network conditions?

How does the application (app) shell of a Progressive Web App (PWA) improve performance in poor network conditions?

Answer

•  The app shell is a widely accepted standard that allows PWAs to be downloaded directly from a mobile website.
•  The app shell runs in the background, allowing it to pre-load dynamic content for faster performance.
•  The app shell runs key JavaScript files, which can be used in place of dynamic content normally downloaded over a network.
•  The app shell stores (caches) the key user interface elements on the mobile device.

A client reports issues viewing their site on a popular mobile phone, but it appears fine on a different device. What should be your first tool to diagnose this?

A client reports issues viewing their site on a popular mobile phone, but it appears fine on a different device. What should be your first tool to diagnose this?

Answer

•  Android test
•  Browser test
•  Explore Impaired networks
•  Device emulation

You want to explain to your boss why the company should invest in mobile site optimization and improvement. What should you say?

You want to explain to your boss why the company should invest in mobile site optimization and improvement. What should you say?

Answer

•  "Improving our mobile site leads to better quality of rich-media assets."
•  "Mobile site improvement slows down our site leading to a higher quality mobile experience."
•  "Mobile optimization leads to decreased advertising spend and higher user engagement."
•  "More customers finding and using our mobile site directly correlates to increased revenue."