In the iOS 15.4 blockbuster update released this week, Apple introduced many features including Face ID that supports masks. For a complete introduction, you can refer to the previous articles on this site. One week after the release of iOS 15.4, more and more users reported that iOS 15.4 had serious power consumption problems.
Every time Apple releases an iOS update, iPhone users start complaining about battery life issues. It appears iOS 15.4 is no exception, as Twitter is full of complaints about heavy battery drain. As the Daily Mail points out, battery drain is usually not permanent.
In fact, ZDNet’s Adrian Kingsley-Hughes explained why the battery drains back in 2020:
Installing a new OS on an iPhone triggers a lot of things in the background, from indexing to recalibrating the battery, which can take hours or even days. Not only does this drain power, but battery recalibration can give the impression that the battery is draining faster, when in fact it isn’t.
Combined with the double factor of the large number of app updates that take place after a new version is released, coupled with the emergence of many new features, it may bring more drain on older phones.
Basically, give your iPhone a few days to recalibrate before you start panicking. Chances are your battery life will return to normal soon. Of course, depending on how old your phone is, your battery may have started to degrade.