RIM's BlackBerry App World isn't the only way to get mobile applications onto your BlackBerry smartphone, but it's one of the most convenient. As the official BlackBerry storefront, there are certain advantages to using RIM's App World. Programs are easy to find by browsing through categories or searching--and only those apps compatible with your phone model will show. You're able to View reviews and see screenshots before committing to an app; you can add your own 2 cents' worth once you've installed the program in question.
While RIM manages no return policy, developers have the option of publishing trials, so you can evaluate a premium application before you purchase. At this time, the only way to purchase apps is through a PayPal account. We'd prefer more options, like linking a credit card with the app store, or using carrier billing.
Apart from that, RIM got one important element right. The My World tab on App World logs your purchases and freeware downloads, making it easy to redownload apps you've uninstalled, and to reinstall all your apps anew if you change phone models.