PiCAST 3 is out, but from what I can tell only streams YouTube videos? I may be wrong, but I haven't have much experience with it.
You can find it here:
https://github.com/lanceseidman/PiCAST
shairport-sync is an iDevice version which will allow you to setup AirPlay to stream audio to your device. However, if you are lucky enough to still be on iOS 8.xx you will also have the ability to mirror your display. Unfortunately, with the newest updates from Apple, the mirror functionality doesn't work from any devices running 9.xx +
You can find it here:
https://github.com/mikebrady/shairport-sync
UV4L is another option. However, it looks as though it requires a bit more work to setup each time and isn't as simple as shairport-sync, but it does allow for video 'casting'. You can find it here:
http://www.linux-projects.org/uv4l/
OSMC has built casting that may work for an android device, being an apple user I am unable to test whether or not it works, but others have reported it working:
https://discourse.osmc.tv/t/cast-youtube-to-kodi-r-pi/7237