You may need to use the remote to wake up the AppleTV if it is not responsive. Point the AppleTV remote at the device and click the menu button to wake it up. You can reboot the AppleTV (if needed) by holding down the Menu and Down buttons for approximately 6 seconds until the AppleTV’s light flashes slowly indicating it is restarting.
Android users will need an app to connect to AppleTV. There are many of these, you will have to determine which is the best for your use. Note that the name of the Apple TV corresponds to the display you are using. At some point in the connection process there will be a code displayed on the TV, type it in on your screen and tap OK.
How you use AirPlay Mirroring depends on what version of the iOS you’re running. On iOS 5 or 6, double tap the iPhone or iPad’s home button to bring up the fast app switcher. On iOS 7 or higher, swipe up to reveal Control Center.
On iOS 5 or 6, swipe the fast app switcher to the right. The first time you do this, you’ll reveal the music controls and rotation lock button. From that screen, swipe to the right again. This will reveal the AirPlay button on the right (and a volume control on the left).
On iOS 7 or higher, you’ll see the AirPlay button on the right-hand side of Control Center.
Tap the AirPlay button. In the list of devices that appears, tap the name of the Apple TV that corresponds to the display you are using
Move the Mirroring slider to On (in iOS 5 or 6) or to green (in iOS 7).
There will be a code displayed on the TV, type it in on your screen and tap OK.
Your device is now connected to the Apple TV and mirroring will begin (sometimes there’s a short delay before mirroring starts up).
Now when viewing content in Photos, Videos, or the Safari app, it will be streamed to your Apple TV.
To get full AirPlay features, make sure your AirPlay-enabled devices are using the latest software updates.
When AirPlay is enabled from Control Center, it will stay on until turned off. Therefore this setting will extend to all apps when used.
You can also AirPlay videos, music, or photos from a variety of different locations on your iOS device, including from within the Photos, Videos, Safari, and Music apps, or directly from recently used apps.
To AirPlay video or photo content to your Apple TV:
Connect your iOS device and Apple TV to the same Wi-Fi network.
Open either the Music, Videos, Safari, or Photos app on your device.
Locate and tap the AirPlay icon (if attempting to AirPlay video content from Safari or Videos, begin playback first).
Select your Apple TV from the list of available devices that appears. There will be a code displayed on the TV, type it in on your screen and tap OK. You can now begin playback.
Updated 7/11/16 (Vgalindo)