Apple has (somewhat smugly) claimed that the Apple Watch has an “all-day battery life”. To find out what they really mean by this you have to dig deep into product manual, spoiler: it won’t last you all day.
Apple defines the Apple Watch battery life in the product manual. According to the page, the “all-day battery life is based on 18 hours with the following use: 90 time checks, 90 notifications, 45 minutes of app use, and a 30-minute workout with music playback from Apple Watch via Bluetooth, over the course of 18 hours.”
Now I’ll forgive them for using clever wording to deceive us, every company does this and sure it’s not an outright lie if you don’t use the watch it will last all day. In fact when the Apple Watch’s battery drops to a determined level, it automatically switches into Power Reserve mode, allowing the device to tell the time for up to an additional 72 hours.
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But the whole 18 hours life (which I feel I should point out apple, is not A day) is only applicable if you use the Apple Watch for what I estimate to be a total of 2.5-3 hours. For specific usage the life will vary. Apple states that the Watch’s battery can last up to seven hours during a workout when heart rate sensor is turned on. When playing back music, the battery will last up to 6.5 hours and up to 3 hours when the Watch is used for phone calls. However, if the Watch is used as a watch, the battery can last up to 48 hours. Apple also states that it takes 1.5 hours to charge the Watch to 80% and 2.5 hours for a full charge.
This is to be expected though, it’s not as though the other smartwatches fare much better on the battery front. But I forget to charge my phone every night so the chance of me remembering to charge my watch are little to none. I’ll stick to the convenience of an analogue watch which charges itself as I wear it.