If you have a 3rd or 4th generation iPod Touch. iPhone 3GS or GSM based iPhone 4, the iOS 4.3 update is now available for download. Just attach your device to your computer, click your device in the left-pane of iTunes and click Update.
This update brings the following changes:
Share iPhone 4 cellular data connection with up to 5 devices (combination of up to 3 Wi-Fi, 3 Bluetooth, and 1 USB)
iTunes Home Sharing
Play music, movies and TV shows from a shared iTunes library on a Mac or PC (requires iTunes 10.2)
New AirPlay features
- Play videos from the Photos app including the Camera Roll album, iTunes previews, enabled third-party apps and websites on Apple TV
- Play slideshows from Photos on Apple TV using transitions available on Apple TV
- HD video out using the Apple Digital AV Adapter
- View 720p HD videos from Videos app, iPod app,Photos, YouTube, Safari, Keynote, and enabled third-party apps on an HDMI display
Push notifications for comments and follow requests Post and Like songs directly from the Now Playing screen
- Messages setting for number of times to repeat an alert
- iPad side switch setting to lock screen rotation or mute audio notifications and sound effects
- Single tap conference call dialing with a pause to send a passcode.