Samsung stuffed an 800mAh battery into the Galaxy Watch Ultra 2, 35% bigger than the original, while making the watch 12% thinner. Then it rated the same 100-hour power-saving runtime as last year. Either the estimate's conservative or the 5,000-nit screen and new features eat the surplus. At $699 with dive certification and a Mares diving app coming later in 2026, it's built for people who won't complain about the price.