Members of Apple's registered developer program were supplied with the pre-release beta builds of iOS 9.3.2, OS X 10.11.5 El Capitan, tvOS 9.2.1, and watchOS 2.2.1 on Wednesday.
All four beta releases are now available via Apple's developer portal website. Registered devices can also access the updates over the air via Software Update.
iOS 9.3.2 beta 1 is identified as build 13F51a. OS X El Capitan 10.11.5 beta 1 is build 15F18b.
Apple's first beta of watchOS 2.2.1 carries build number 13V413, while tvOS 9.2.1 is build 13Y5742b.
The 0.0.1-level upgrades for all four builds would suggest that Apple is planning to squash bugs and fix issues rather than introduce new features. The company typically saves new features for both point-one releases.
Future major updates to Apple's platforms are more likely to be introduced at the company's annual Worldwide Developers Conference in June. It's there that Apple is expected to unveil iOS 10 and OS X 10.12, though recent evidence has suggested the Mac operating system could be rebranded as "macOS."
The last publicly released iOS update was iOS 9.3.1, issued less than a week ago to fix a Web link crashing bug. OS X 10.11.4 brought Live Photos and improvements for Notes and iBooks with a public release last month.
Also issued last month was watchOS 2.2, featuring support for pairing multiple Apple Watches to a single iPhone. It also improved the Apple Maps glance, making it easier to get directions on the wrist-worn device.
Finally, tvOS 9.2 also publicly launched in March, adding support for app folders and voice dictation. It is available only for the new fourth-generation Apple TV.