I cannot get air play icon on my iOS devices please help

Is airplay enabled on ATV? Are the devices on the same network? Is everything up to date?

Try reading the article from which the question was posted and following the troubleshooting steps listed there. It explicitly details how to troubleshoot the issue occurring.

I have done all that and still no air play icon. what now??

Has all the troubleshooting steps in the article linked at the top of this thread been tried?

In IOS 7, the air play button lies below the bottom of the iTunes page. You need to click along the bottom for it to come up. Air play is there! Wow! I spent so much time trying to figure out what was wrong and as usual, it was me!

Yeah, it was moved to Control Center in iOS7.