While people who have used both iOS and Android devices will argue over which OS exhibits a greater degree of polish, Android definitely has the better notification system. Even the addition of multitasking to iOS 4 did little to improve the state of notifications on iOS devices compared to Android.
Boxcar, which just reached version 4 on the App Store, is a great improvement over standard iOS notifications. Boxcar enables super-fast push notifications for services ranging from the internal mail app to Buzz, Twitter, Facebook, and Google Voice. An ad-supported version of Boxcar is available for free, but an in-app purchase of US$4.99 will eliminate the ads. The app is so good that TechCrunch's MG Siegler thinks Apple should just buy Boxcar and incorporate it into iOS. At the very least, Apple should take some inspiration from Boxcar's features for iOS 5.
[via Daring Fireball]