Apple is now officially rolling out the all-new iOS 9.2.1 to eligible iPhones, iPads and iPod touch. This software does not bring big, conspicuous features but it is teeming with tweaks and repairs, being the first big bug fix update for the iOS 9.

The software is being rolled out over the air to units running the iOS 9 – every iPad mini unit, the iPad Pro, every iPhone iteration starting with the iPhone 4s, the iPad 2 and every unit after that and the fifth and sixth-generation iPod touch.

Apple did not elaborate on what the iOS 9.2.1 has in store, although the update is certainly big on security enhancements. The Cupertino-based company did mention it brings a solution to the Mobile Device Management issue that plagued enterprise customers.

"This update contains security updates and bug fixes including a fix for an issue that could prevent the completion of app installation when using an MDM server," Apple wrote in its change log (via Mac Rumors).

The iOS 9.2.1, however, does not have a fix for the time zone bug that prevents the battery percentage indicator to update accordingly. As per Arstechnica, Apple was already notified of the concern and is now looking into the matter.

An official fix for it is still being developed by the tech giant. Until then, users snowed under this issue can try a temporary workaround Apple has provided on its Support page. To learn more about the Apple iOS 9.2.1, click here and here.

The iOS 9.2.1 comes a month after beta versions for it were released to beta testers and developers. Apple's attention is now turned to the iOS 9.3, whose first beta version was made available a week back to members of Apple's beta testing program.

The iOS 9.3 will be a major update as it contains new Night Shift mode and other exciting features. It will be rolled out in spring.