The Smartphone Gets Smarter: Mobile Apps for Entrepreneurs The deluge of mobile applications -- some genius, some garbage and some just plain goofy -- continues.

Smartphones are redefining the concept of business intelligence. Tech-savvy entrepreneurs are tricking out their mobile handsets with applications designed to ease and improve every conceivable facet of their professional lives. Market research firm Compass Intelligence forecasts that American SMBs will spend close to $350 million on mobile software this year alone, downloading everything from basic office utilities to customer management solutions.

The sheer quantity of mobile applications optimized for entrepreneurs is impressive, but the quality not so much. You could say there's an app for everything except for identifying the small-business apps worth downloading. As of mid-2010, Apple's pace-setting App Store had more than 225,000 iPhone applications, but the number of innovative and useful apps is far smaller. Add in the overwhelming volume of consumer-centric offerings like games, e-books and novelty apps, and it becomes even tougher to identify and evaluate which applications best meet your startup's demands.

That's why Entrepreneur turns the spotlight on 25 of the most revolutionary and vital applications on the market. Given developers' focus on the iPhone, it's no surprise that many of the apps are synonymous with Apple's iOS platform, but our list also makes room for applications created for Research In Motion's BlackBerry, Google's Android, Microsoft's Windows Mobile and other rival operating systems.