iOS includes several useful tools for displaying how much battery life your iPhone has left, as well as which apps are consuming the most of your battery. However, none of these tools actually tell you anything about your battery’s long-term health, which is just as important.
Battery Health vs. Battery Life
Battery health is different than battery life. Battery life determines how long your battery lasts on a single charge, but your battery health determines how much your battery life diminishes over time. After a year, your battery life won’t be as long as when the phone was new, and it will continue to degrade as the years go by.
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