You probably don't really need AppCounter, an app that lets you keep tabs on what's hot and what's not in the Windows Store. But it's a compelling download, especially for anyone with a stake or interest in Microsoft and its entry into the app universe. AppCounter tracks key stats and the general progress of the Windows Store. For example, you can see app categories ranked by quantity. (Education is currently in the lead, followed by Entertainment, Books & Reference, Games, and Tools.) Is it the most productive app ever? Nah. But it's an interesting, quick scorecard for charting the Windows Store's growth.