This is part of a larger design and product overhaul.
YouTube, in its official blog published on August 29, 2017, announced a series of design changes and unveiled a new logo. "Designed for our multi-screen world, the updated logo combines a cleaned-up version of the YouTube wordmark and icon, creating a more flexible design that works better across a variety of devices, even on the tiniest screens," writes, Neal Mohan, chief product officer, YouTube.
His blog further states, "Why's it more flexible? When room is limited (say on a smartphone) you can use the brightened-up icon as an abbreviated logo, which will be seen more easily and read more clearly. You'll see the new logo and icon roll out across mobile and desktop today, and across all our other apps and services soon."
Apart from the new icon and updated logo, YouTube has refreshed its desktop version, unveiled a new dark theme and will soon redesign its app too.
"When YouTube launched 12 years ago, it was a single website that supported one video format, 320x240 at 4:3 aspect ratio. Fast forward to present times, where YouTube lets you watch any combination of SD, HD, 4K, 360, 3-D, and live video on nearly every device with an internet connection - from desktops to phones, tablets to TVs, game consoles and even VR headsets.
To put it simply, YouTube's evolved... a lot. And we're not even close to done. Over the last few months we've started releasing updates and will continue to throughout the rest of the year. When all is said and done, we'll bring a new level of functionality and a more consistent look across our desktop and mobile experiences," wrote Mohan in his blog.