New Features in iOS 4.3

Some of the new features integrated in iOS 4.3 are:

AirPlay: Limited Web Video Support Added. AirPlay enables near-real-time streaming of certain videos and photos.
The web-based videos will stream only when they are authorized and a permission tag is necessary for iOS 4.3 before allowing the video to stream.
Audio from unauthorized videos can still stream any way.
Self-made videos stored within the Photos application can be streamed through Apple TV now in 4.3.

New features in iOS 5

All your alerts can be set in one place. All types of notifications like new email, texts, friend requests can be tracked easily now in one location. Even the lock screen displays notifications so that one can act on them with just a swipe.
All to-dos can be listed systematically in the iPhone with the help of reminders. You can record your due dates and locations. It can be location based which means there will be an alert once you reach the supermarket. It can be synced via Outlook or iCloud too.
You have the newsstand in one place. Your magazine and newspaper app subscriptions are organized in Newsstand. With new issues, the Newsstand gets updated in the background like the newspaper coming to the door.
Now you can capture those unexpected moments which would get lost till you set the camera to the best position. The camera app is right from the Lock screen, and is adorned with pinch-to-zoom gestures, and single-tap focus. Press the volume-up button to snap your photo within seconds.
You can set up all your devices wirelessly, right out of the box and even back up and restore your device with the help of iCloud.
In iOS 5, Airplay supports video mirroring which implies that you can wirelessly stream whatever’s on your iPad 2 to your HDTV via Apple TV.