Smaller batteries, same battery life?
As a rule of thumb, Apple products have smaller batteries than their conterparts made by other manufacturers. No only this, but Apple with every new generation continues to shrink batteries in their own devices. The iPhone XS now has a smaller battery compared to last year's iPhone X, and even the Apple Watch Series 4 has a smaller battery than the Series 3.
Apple stated that the 44mm Series 4 has 1.12 watt-hours while the 40mm version has 0.86 watt-hours. Last year's Series 3 42mm model had 1.34 watt-hours and the 38mm had 1.07 watt-hours. This is a significant drop – 16.5% in bigger devices and 19.7% in smaller.
Although this is a significant drop, Apple claims that new devices will be capable of lasting the same time – 18 hours of use. We cannot just blindly take their word for granted – it will have to be tested.
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