Is it possible to record calls on Galaxy S3
I used to use Auto Call Recorder as well (before my S3), and I was highly unsatisfied when it stopped working (when I switched to S3).

Just yesterday I found out this another great app that just works. And seems like much better than ACR: Record My Call - The solution! No idea how that's even free (even if it does have ads). And, I do have root, but I think this doesn't even need it.