Yep, that's just one good reason why many people are eager for a useful smartwatch. I.e. one that not only remotes many app / phone info, but also works standalone and has very long battery life. Alas, so far, I haven't found one with all those qualities yet.
Finally, take a look at flexible LCD technology that's on the verge of a widespread launch. Now pair that with a wide wristband and you have a device approximately the same width as a men's wristwatch at its widest with the same screen real estate as an iPhone 5 with no restriction on movement.
Philips electronics recently showed off such a concept, called the Fluid:
And here's an another flexible phone concept. Could be handy for wearing in back pockets - grin:
Wearable phones are an old idea. Here is one that IBM showed off back in 2000:
A jewelry set where the microphone is in a necklace, with matching earrings that are tiny headphones. The ring has an LED indicator to alert you that a call is coming in. An optional bracelet lets you see who is calling and/or show other data like appointments: