Yeah, it looks like the Android it's running is several generations old. But I'm not trying to use it as a cell phone either. I have a few other (non-ham related) devices that use Android that's old and it seems to be fine for purpose-built devices.
I've seen some other posts that talk about the interface being a bit confusing/clumsy. And some other discussion about audio quality.
Of course, lately I've been seeing stuff about the new M6 which is what has me curious again...