While neither model is really a smartwatch, the FES Watch U does have a little more functionality than the original model, with extra face designs available by connecting to an app called FES Closet. Sony says it will release new designs from notable creators every month for the rest of the year. The new watch also uses a rechargeable battery that lasts up to 3 weeks; the original FES Watch used button cells that had to be replaced every couple of years.