AppCrawlr - Discovering new applications
AppAgg - Application Aggregator
AppShopper - Mac Apps, Mac App Store, iPad, iPhone and iPod touch app store listings, news, and price drops
AppAdvice - AppAdvice is the leading online and 'onapp' resource covering all thing iOS
BlackBerry App World - Get apps for your BlackBerry with App World.
Apple Sliced - Apple Sliced searches the Web for the lowest prices and uses only Authorized Apple Resellers, so...