Air Server on my Mac turns my Mac into a Airplay device - just like having an Apple TV connected to a television. This means that any Apple mobile device on the same WiFi network as my Mac will see this Mac is the list of available Airplay devices.
I have used Air Server for years now and can highly recommend it!
Yosemite brings an eleventh option for projecting your iPad or iPhone screen
Read about this new feature of iOS 8 and Yosemite - one that uses Quicktime Player 10.4 on your upgraded Mac. I'll be going into more details about this great new feature in a future blog post!