A:Answer There's not much real world data yet, but per androidauthority.com: "Samsung says all Galaxy Watch 4 devices, no matter which size or model, should last around 40 hours with regular use. We assume that's with typical use in 'smartwatch-only' mode (i.e., no GPS tracking)..." and "...when you're low on battery, leaving the watch on the charger for 30 minutes will supposedly earn you 10 hours of usage."
