Screenshot by Lance Whitney/CNET

Microsoft on Tuesday started offering a preview of its Office apps for Android tablet users, no invite required.

The apps include preview versions of Word, Excel and PowerPoint designed specifically for Android tablets. In a blog posted Tuesday, Microsoft's Office 365 team spelled out the requirements to install and run the apps, notably an ARM-based Android tablet with KitKat or Lollipop and a screen size anywhere between 7 inches and 10.1 inches.

Microsoft has made a concerted effort lately to expand the scope of its Office apps to Android and iOS users to gain more market share for its popular suite. That's a decided contrast from the past when the company focused more on the Windows and Windows Phone versions of Office, and support for iOS and Android was an afterthought.

Microsoft introduced an Office Mobile app for Android in 2013, but only for smartphones and only for Office 365 subscribers. Also unveiled in 2013, the iOS version required an Office 365 subscription as well. In November, Microsoft opened the doors so that you could create and perform basic editing tasks on the new separate apps for Word, Excel and PowerPoint for free. And in a savvy , the company still required an Office 365 subscription for you to perform more advanced editing chores.

At the same time, the software giant launched a preview of its new Office for Android tablets. But the preview required you to sign up to receive a special invitation to try it out. Now Android tablet users can simply download the previews of Word, Excel and PowerPoint from Google Play.

As expected, the apps are freemium versions, meaning you can create documents and perform basic editing. But you'll need that Office 365 subscription to do more.

The versions available are still previews, meaning unfinished products that Microsoft wants Android users to check out and offer their feedback. In its blog, the Office 365 team said that "we want more feedback from more users to ensure that Office apps work well on a range of different Android tablets before launching the official apps." You can share your feedback in the Google+ community for the Microsoft Office for Android Tablets Preview.

The finished version of Office for Android tablets will be available in the first half of 2015.