Apple has seeded Mac OS X 10.7.3 to developers, asking them to focus on iCal calendars, Mail, AddressBook and iCloud's document storage.

OS X Lion 10.7.3 build 11D16 is reported to have no known issues and is 633MB. It comes alongside a pre-release copy of OS X Lion Server 10.7.3, reports Apple Insider.

Macworld Feature: iCloud - what you need to know

iCloud's Documents in the Cloud, one area that devs have been asked to focus on particularly, lets you keep documents synchronised across your Mac, Windows PC, iPad, iPhone or iPod touch provided you have the same iCloud-enabled apps installed on each device.

Mac OS 10.7.2 was made publicly available just over a month ago, on the same day as iOS 5. It was the first version of Mac OS X to bring iCloud functionality to the Mac.

There is no indication yet as to when Mac OS X 10.7.3 will be available to all.