Re: They don't require you to wear them "all the time"
You both are making good points. The basic problem on glasses is going to be what it has always been, vanity. People generally don't want to wear glasses, which is why to a large extent, the contact industry has been going strong for years. If people can be conditioned to think they look better with these things on their faces, as most people do with sunglasses, then perhaps this will have some success. I expect what will be most likely to happen is that the design will be a bit of an origami, where they can fold down flat like today's phones, but then change so that they can be used as glasses when desired.