Microsoft announced Tuesday that registration for the Microsoft BUILD developer conference will open on Jan. 22 at 9:00 a.m. PST, a day after its press event, scheduled for Jan. 21, to discuss Windows 10 and the next evolution of its operating system designed for PCs, tablets and smartphones.

The date is probably a good choice, especially if Microsoft plans to drum up fresh interest in its products the day before, and Microsoft says its "shift to a mobile-first, cloud-first company is in full swing." Microsoft announced earlier that its BUILD conference will kick off on April 29 and will run through May 1 at San Francisco's Moscone Center.

"This year's BUILD will lay out how you can be the most productive and creative developer you can be and showcase the latest tools and technologies you'll be using to get it done," Microsoft's corporate vice president of developer experience and evangelism, Steve Guggenheimer, said. "You can expect some fun surprises along the way as well."

It's likely BUILD will focus not only on Windows and Azure, but how developers can develop applications designed to run across Windows 10 for smartphones, the desktop and tablets as smoothly as possible. We expect to learn more about that operating system Jan. 21.