[Update, Tuesday morning: Microsoft’s Office 365 announcement is now out, detailing the updates to the subscription service, but the company isn’t providing any update on Microsoft’s plans for Lync mobile apps, at least not yet. I’ve updated the post below, and I’m checking with the company for more information.]

[Update, Wednesday morning: A Microsoft representative says Lync mobile apps will be available by the end of the year.]

Microsoft is getting ready for the debut of the first mobile apps for its Lync communications service — including versions for Android, Windows Phone, iPad and iPhone — judging from various clues that have been surfacing online.

The debut of the mobile apps will be an important step for the Lync business communications tools, which include instant-messaging, email and conferencing, among other features.

A version of Lync is part of Microsoft’s Office 365 monthly subscription service, which is going head-to-head with Google Apps for business customers. Mobile access is critical for many of those customers.

The company on Tuesday will be announcing the first major service update to Office 365, while adding new features and 22 new markets.

That’s according to a tweet from the official @Office365 account tonight (pictured at right) that has since been removed.

Before it was taken down, the tweet pointed to a link for a page that is not yet live. The url for that page indicates that the company will also tout a record growth rate for Office 365 as part of the announcements. IDG News Service is reporting similar advance details, quoting anonymous sources.

[Update, Tuesday morning: Here’s the official news release, now live.]

Microsoft has previously signaled plans to come out with Lync apps for mobile devices, including Windows Phone and iPhone, but the timing of the release wasn’t previously known.

The company says on the Lync web site, “Microsoft-developed Lync clients will be available for Windows Phone 7 and iPhone, jointly developed clients will be available for Nokia phones, and partner-developed clients will be available for other smartphone platforms.”

Microsoft’s Australian unit recently confirmed on Twitter that Lync would be coming to Windows Phone, Blackberry, Android and “iDevices” within a matter of weeks.

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