Chapter #79. Make Your Favicon Distinctive
A favicon, app icon or "apple-touch-icon"—whatever you call it—is an icon you may well have forgotten to add to your web app. It serves a useful purpose beyond branding.
Users with lots of tabs open, lots of apps in their start menu, or lots of apps in a folder on their phone, will appreciate being able to find yours quickly.
A bright, bold icon or letter is usually sufficient, but test it at 16 pixels in size to see that it's legible. Use transparency well, unless your icon actually is a square—nobody wants an ugly white square in their tab bar.
If users can see your app instantly and switch to it, you'll be saving thousands of hours of people's time cumulatively. Good job!