Microsoft has gotten itself head-deep into the mobile industry with Windows Phone 7, and perhaps to a broader extent with the upcoming Windows 8 due sometime in 2012. In addition the company made some of its apps available for Android and iOS, a tactic that GigaOM’s James Kendrick believes extends beyond plain competiveness.

Kendrick’s theory is that making its software available for competing platforms is an effort by Microsoft to keep the competition at bay, and its dominance with Windows and Office around for a while longer at the same time. It’s unknown whether the company intends to reiterate this approach in yet another sector when co-founder Paul Allen’s space venture will launch in 2015, considering that both Android and iOS handsets have already breached the earth’s orbit.

“People are already discovering that a number of office suite apps exist for both the iPad and for Android tablets. These apps are pretty darn good, and even offer a good level of compatibility with existing Microsoft Office documents. Tablet users are finding them to be acceptable replacements for the Microsoft software they thought they had to have. Once they make the switch on mobile devices, it is only natural to do so on the desktop, too.”

This may as well account for a portion of Microsoft’s motive in the mobile industry, but the opportunity of tapping this rapidly-growing and already multibillion space  is most likely the more prominent temptation.  So much so that analysts from Danske Bank believe Microsoft may be bidding for Nokia’s smartphone business. The deal could be announced as early as the first half of next year, the analysts said, putting a price tag of $19 billion on the Nokia unit.

There’s a high likelihood that such a deal won’t take place, especially in light of the two companies’ existing partnership, but this speculation does act as another sign of Microsoft’s seriousness with its mobile strategy. Another recent indicator of that is a rather creative Twitter campaign asking Android users to submit their malware infection stories to Microsoft, for a chance to win a Windows Phone 7 device.