Apple has made iOS 4.3 available before the original launch date and ahead of the iPad 2 hitting stores on 25 March.
Users can now connect their Apple devices to iTunes to download the updated operating system, whether they have an iPhone, iPad or iPod Touch.
Apple announced the new OS would be available from 11 March alongside the iPad 2, which will be on sale in the US from tomorrow.
For an unexplained reason, Apple has released the update sooner.
Users will be able to take advantage of a range of new features with iOS 4.3.
iPad 2 owners will also be able to customise the iPad switch to be a mute or rotation lock, rather than just have the mute option as on iOS 4.2. Personal hotspots have been enabled with the OS.
The business response to the iPad 2 has been somewhat mixed.
IT PRO's recent analysis found some bemoaned the lack of any exciting new business functionality, whilst others praised the extra power and FaceTime addition - thanks to the new cameras.
iPad and iPhone owners have been advised to update to iOS 4.3 for security reasons.
A range of critical security patches have been included in the update, covering vulnerabilities which could have allowed hackers to run malicious code on the Apple devices, Sophos warned.
Security issues included multiple memory corruption issues in WebKit, which could be exploited to execute unauthorised code when users head to malicious websites.
The iOS 4.3 update is compatible with the iPhone 3GS and later, the iPod touch 3rd generation and later, as well as all iPad models.