Stream tablet to computer with switcher to stream to internet I was unsure where to post this, so please move if there is a better site for it

I am trying to design a cheap system that allows me to have 3 video inputs, allows me to mix them and stream it live to youtube.

Currently I am thinking that I can stream from basic amazon/android tablets to a central computer running OBS. I could mix and apply effects and then stream from OBS to youtube.

My main question is how would I import a stream into OBS and how to create the stream on the tablet.

Overall I would prefer a solution that already exists, but would be able to create an app to do some of the work.
So possibly OBS (i havnt checked) as CasparCG (im using) do not support stream producers (input), I was recently looking into this option, and one program i found (there may be others) that supports this is vmix http://www.vmix.com/software/features.aspx which has a free version.