There have been a few input device ideas over the past months that continue to overlook the blatantly obvious, and that is that the input device is more closely linked to the owner than the gadget in question.
The solution is customise your own input device that you can take from computer to computer
or phone to new phone. I posted a couple of variants on this idea, but they got deleted a while ago.
Anyway, imagine a bluetooth device that acted somewhat like a keyboard. It would have extensions for media keys, but would go further to have any other kind of meta action e.g. meta: render.
And this is exactly the point where you as the user of the input device take total control. If you assign a meta action to a particular button etc, the keyboard will always generate the code you assigned. The problem now is to get your computer or gadget to recognise it e.g. by configuring a hotkey program. But what is easier ? Training your muscles to reach for a different key when you buy a new computer or to do a one-off configuration ?
This might not seem such a big deal yet, but when you consider enhanced data rate input devices such as chording keyboards, you don't want to learn a new scheme when swapping hardware. You choose your optimal input device and run with it until you want to retrain your reflexes.
Lastly, (and a direct copy of a previous idea of mine), the input device need not have conventional buttons at all, but nerve sensors you could place wherever you have nerves left (in case you are missing a few limbs etc). Foot pedal + left eyebrow = meta: render.
A future standard may cover meta actions or feedback - you don't need much more than the current item name. meta: folder, next, next. meta: file, next, next. meta: open.
I realise this may be somewhat baked by various interfaces for the disabled, but there is no reason why it cannot be extended for the average person. Imagine buying a new gadget and not having to learn new key combinations for functions that haven't changed.
Computer or gadget - someone elses design.
Interface - your own personal standard.