A patent application by Microsoft shows that the company is hard at work improving mobile phone design to match their many uses, including playing games. The document describes a two part design comprised of a primary handset accompanied by a similarly sized potentially detachable, modular unit. Of the uses illustrated for this secondary section, one of the more interesting is a dedicated game controller.

To date, Microsoft has stayed out of the hardware side of the mobile business, instead partnering with manufacturers such as HTC and Samsung to create Windows phones. Nothing in the patent documentation indicates a change in that stance, but it likely does indicate how Microsoft envisions the next evolution of the platform and the features that will be supported in their mobile operating system.

The basic premise for the patent (spied by Mobile Magazine via Eurogamer) rests on the idea that users want a way to use the many functions of their phones, while conducting a call in the old-fashioned, hold-it-up-to-your-ear way. For this reason, the second piece can be detached, so it can be used while still talking on the handset piece. One of the main suggested uses for the second part is a second screen, on which one could surf the Net easily without having to pull the phone away from their ear. Other potential uses mentioned include a keyboard or extended battery. When detached, the two devices would communicate wirelessly.

Adding a controller panel to a phone isn’t a shocking innovation but Microsoft’s patent does show how integral a part mobile gaming plays in the company’s Windows phone plans.