We use and ipad app called Do Ink Green screen.  When we downloaded it, it was free.  It is a great tool.  You can actually record on any color wall and then just change the chromakey to match it.  We actually use our hallway wall to record.  It is painted blue. The app can save the video to the camera roll and then the final product can be exported to the student's google drive.This is a video I share https://www.youtube.com/watch?v=LWAHxtpPp24

I have also sewn together large pieces of felt, from our home ec. dept. and hung them throughout our LLC for recording.

Hope this helps,

Kim Moran

Technology Integration Teacher

Ridgefield Public Schools.