When reports emerged that struggling smartphone maker Nokia had considered building devices based on Android, few questioned the firm's rationale for at least testing the waters. But when later reports suggested that the firm was still actively working on Android devices, more than a few eyebrows were raised. It turns out, however, that Nokia's Android experiments have nothing to do with replacing Windows Phone. And Microsoft might very well continue the efforts once it acquires Nokia's devices and services businesses.

If this isn't about Windows Phone, then why is Nokia experimenting with Android?  It turns out that the firm is instead looking for a suitable replacement for its low-end, entry-level Asha smartphones. Those devices currently run on the ancient Series 40 mobile OS, which is based on Symbian and dates back to the late 1990s.

Related: "Nokia Worked on an Android Handset? Obviously!"

According to a reliable report in All Things D, Nokia is using Android because it's free and can be modified to any degree desirable. The resulting project, alternatively called "AoL" (for "Asha on Linux") and "Normandy," aims to replace the aging Asha underpinnings with something a bit more modern while ostensibly retaining the standard Asha look and feel and app compatibility.

Because Microsoft is purchasing all of Nokia's device platforms—the Nokia-branded "dumb" phones as well as the Asha smartphone and Lumia smartphone and tablet lines—the software giant will ultimately decide the fate of these possible Android-based Asha successors. And various reports, including the one in All Things D, suggest that it might very well continue the project.

The other alternative, of course, is that Microsoft could simply provide a scaled-back version of Windows Phone for future Asha devices. That might actually make more sense, given that the product line is aimed at customers who can't afford Lumia smartphones or the expensive data plans that modern smartphones require.

And with Microsoft considering making a combined Windows Phone/Windows RT available freely to device makers—which I first wrote about earlier this week in "Big Changes Are Coming to Windows"—such a move would be less prohibitive and would open up the possibility of licensing the OS for the types of third-party, entry-level smartphones that are popular in emerging markets.

Still, using Android has its advantages, and with Microsoft already porting most of its mobile apps to that platform now, making them available to next-generation Asha handsets would be fairly straightforward. And this would provide a hedge in the event that Windows Phone never captures double-digit market share: Microsoft could always fall back on its Asha/Android hybrid should the need arise.