Hello there pdm29,
It sounds like you installed a software update for iOS 7 and now you cannot access Airplay from the Control Center anymore. I found this article that should help you get that resolved named:
iOS: Troubleshooting AirPlay and AirPlay Mirroring
http://support.apple.com/kb/ts4215
- Verify that your iOS device's software is up to date.
Verify your Apple TV's software is up to date.
- Verify that your iOS device has Wi-Fi turned on. Enable Wi-Fi on your iOS device by going to Settings > Wi-Fi.
- All AirPlay-enabled devices must be connected to the same Wi-Fi network.
Some Wi-Fi network configurations offer a Guest Network. On your Apple TV, go to Settings > General >Network and ensure that you're connecting to the same Wi-Fi network on your iOS device. On your iOS device, tap Setting > Wi-Fi and confirm that this matches your Apple TV.
Ensure that you have followed the steps in using AirPlay and AirPlay Mirroring.If you are still unable to see the AirPlay icon , try one of the following steps:
But it is always a good idea to restart all devices involved including your network router.
Apple TV: How to restart your Apple TV
http://support.apple.com/kb/ht3180
iOS: Turning off and on (restarting) and resetting
http://support.apple.com/kb/ht1430
Thank you for using Apple Support Communities.
All the very best,
Sterling