The latest updating from Apple support page, guided user to send content from iPhone 4S or iPad via Apple TV to HDTV with the AirPlay Mirroring function. For the best output effects, make sure you configuration meet the minimum system requirements of AirPlay Mirroring:
--iPhone 4S or iPad 2(or later generation) with iOS 5 or later
--Apple TV (2nd or 3rd generation) with software update v5.0 or later.
--AirPlay Mirroring requires either a Wi-Fi (802.11 a/g/n) connection or an Ethernet connection to the same local network that your Apple TV uses.
1. Under the same WiFi network, connect your iPhone/iPad to your Apple TV
2. Click the Home button twice for showing the latest application
3. Slide your finger from left to right to find this icon
4. Click it to show the devices available for AirPlay
5. Click Apple TV and turn on the AirPlay Mirroring, then you can use the function.
Note: The AirPlay Mirroring is only available with the Apple TV (2nd or 3rd generation) with software update v5.0 or later.