Apple Watch: Battery life, iPhone dependence, other troubling issues

The Apple Watch, which is to go on sale early next year with more than 20 different looks and a minimum price of $349, has its share of innovations: A screen made out of sapphire glass on some versions to increase its scratch-resistance. A “digital touch” feature that allows people to give their contacts physical taps on the wrist via the Internet. And an invention Apple compared to the iPod’s click wheel — a watch crown that can be pressed or rotated to scroll, access Siri and return to the main screen.

There were some details, though, that Apple didn’t discuss much Tuesday that could become troublesome for Apple Watch’s success.