I heard rumours that appple watch would delegate all processing to your iphone, in order to preserve battery life, and thus only become a dumb interface. That l

I heard rumours that appple watch would delegate all processing to your iphone, in order to preserve battery life, and thus only become a dumb interface. That leaves me with a question since my iphone itself only has a limited battery life.. Or maybe the watch will be completely unusable without an iphone anyway. Aka no network access, not even wifi, and no local app, or game or anything to be used without a phone. But then, why the expensive price, just for an input/output dumb device ?