App designers have choice -- Apple's iOS, RIM's BlackBerry OS, or Google's Android. That's because the different devices each have their own operating systems. Until now, Apple was the obvious choice. But the others are beginning to catch up.

  Apple Google RIM
Number of apps 286,000 100,000 14,000
Platform market share 24% 21% 37%
Percentage of users who have used at least one app 92 91 86

Sources: ComScore, 148Apps.biz, Google, RIM