Submitted by CommercialThis4987 t3_119y8mf in iphone
I just checked how many battery cycles my iPhone 11 Pro has gone through: 873. This phone was made 08/26/2019, so it's roughly 3.5 years old. Now, I think, is the best time to replace the battery. Why? Because iPhones are supported for 7 years (right?). I would expect the last iOS for iPhone 11 to be released in 2025, so with the release of the iOS in fall of 2026, the iPhone 11 Pro will be obsolete. This means I have 3.5 years left of updates of my iPhone, so I should replace the battery now rather than wait a year to change the battery.
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Is my thinking about this correct? I know some power users may go through cycles more quickly. But I think 1 or at most 2 battery replacements to be optimal if one plans to use an iPhone the entire support cycle.
dskatter t1_j9outfu wrote
The best time to replace a phone battery is when the health goes below 80%, whenever that is.