"Since it's such an important part of our daily lives, we're making a few improvements to Yahoo! Mail," chief executive Marissa Mayer said in a blog post.
"You've told us loud and clear that you want fewer distractions when it comes to email.You want to quickly login, communicate, and get on with your day. And we've listened. Starting today, the new Yahoo! Mail is fast, easy and available anywhere you go."
The improvements will be available over the coming days for Web-based mail as well as on Windows 8, Apple and Android mobile devices.
"We've redesigned the new version of Yahoo! Mail with speed in mind -- getting through your emails is faster than ever before," Mayer said.
"We've also made your inbox more intuitive and easier to navigate, allowing you to focus on what matters most: your messages. And, because mobile is everything these days, Yahoo! Mail now has a consistent look and feel across devices."
Mayer, who moved from Google to become Yahoo! CEO in July, has been repositioning the Internet pioneer to focus more on mobile.