Availability for all platforms

I think if I have 3 friends to come over and I have 2 computers with Minecraft and 1 iPad. How do we play Minecraft? same is you have 4 over. a console (on split screen), an iPad, and a MacBook. there should be compatibility. I know that each version has different blocks, but if there could be a 'standard' setting and if all devices were set to that setting they can pair up and all have the same blocks, textures, and items.

FunnyMode