Give Me Juice
Limited functionality aside, another problem plaguing smart watches is battery life. Regular quartz watches, even multifunction ones such as Casio’s Protrek series and Tissot’s T-Touch series, can easily last for years on batteries. Some quartz watches even use rechargeable batteries that can be charged through solar power or simply by the wearer’s wrist motion, not unlike an automatic mechanical watch. On the other hand, mechanical watches will run so long as they were being worn or wound regularly as they usually offer at least two days of power reserve. Even with the most optimistic outlook of battery saving technologies like E-ink displays and displays that go to sleep when not in use, most smart watches are going to need a charge at least every other day to ensure that it does not suddenly die on you. Instead of a trustyworthy companion device, you end up with just another gadget that requires constant charging for minimal funtionality.
The problem of battery life is not just limited to your smart watch but extends to your phone too. Enabling Bluetooth the entire time will have some effect on battery life, even with the newer Bluetooth 4.0 low power standard. This then becomes a problem for smartphones with average or below average battery life.