I literally don't see the point in a tablet (other than to watch movies) if you have a smart phone, and if you have a smart phone you can also ditch the 'dumb' phone... and then you have the watch and phone with nothing else.
A phone is so easy to displace and forget. They get stolen or lost in other ways.
A wristwatch is always on the wrist, and I won't displace my bag in the first place.
When I want to use the phone as a
phone I would need only the watch and the headset. I would in effect get a smaller phone because it is actually hidden away. You could see the tablet/phablet as a "mobile server" if you will. Another reason for using it is to avoid radiation where as even a Bluetooth headset radiates 1/1000 of what a cell phone does.
For the "app" use-case, a 8" tablet would give me a screen on which I could use many real web pages without being relegated to a "mobile view" or "mobile site". The past few years though, I have also carried an old netbook when travelling - which the tablet is also intended to displace.
BTW, I would not watch movies on either - movies are intended to be watched on big screens.
BTW 2, I am not there yet, but as I get older I expect my eye sight to deteriorate and then I would not be able to use a tiny little screen with tiny text any more.
A smart wristwatch needs to be a better wristwatch than an average smartphone is as a pocketwatch, and that means that it needs significantly better battery use than having to be recharged in a specialized docking cradle every night.
Anyone remember the
6th gen iPod Nano... which was square and the same size as the Apple Watch? There were several third-party armbands available for it so that it could be used as a watch, but it never really became popular as one. The biggest reason was its lack of battery life.