Not so much "playing" as "attempting to exorcise" The Witness. Easily one of the most addictive and interesting puzzle games I've played. On a related note, my computer has been struggling with newer video games, so I've retreated into an older passion of mine: Interactive Fiction games. I could talk about them all day, and I've found some over the past few weeks that have been absolutely phenomonal. Everyone reading this should go play Photopia right now, It is easily one of the best uses of the medium that I have ever encountered.
For the Witness? Not that I've heard. I think they just started work on the iOS port recently, and I haven't heard anything about Android. It's a fairly resource-intensive game, so I don't know if it would end up on a mobile format.