Good news for all iPhone / iPod users who are addicted to Facebook. One Facebook is one of the best apps for the iPhone platform but sadly it did not support multitasking or fast app-switching which came in iPhone OS 4 / iOS 4. Thanks to the latest update (v3.1.4) which is compatible with iOS 4.0.You can now switch between Facebook and Twitter apps or Email without having to start all-over again. Head to the app store now !