Along with iOS 8.2, Apple released Xcode 6.2 for developers on Monday. The update for the app development environment includes iOS 8.2 support, and WatchKit support for developing Apple Watch apps.
Xcode 6.2 with Apple Watch support now available
Beta versions of the updated SDK have been available to developers since February, but this is the first time version 6.2 has been available as an official public release. Developers planning on making apps for the Apple Watch will need to download this update to get the tools they need to get their projects off the ground.
Along with WatchKit support, Apple's release notes say the 6.2 update includes SDK tools for iOS 8.2 along with OS X 10.10 Yosemite.
Xcode 6.2 is free, as is this update if you're running an earlier version. It's available through Apple's Mac App Store as a 2.58GB download.