iPhone Battery Drain

Since updating the software on my iPhone last week, I have noticed a massive battery drain occurring on my iPhone.  If I don’t leave my phone plugged in overnight, it will drop from 100% to <20% power by the morning.  Just ridiculous.  And that is when the phone is not being used.  I don’t imagine I can sustain a long phone call now without using up all the power up.  I first of all thought it might be an issue with the battery.  After all, there had been recent stories of Apple being caught using batteries that degrade quickly to try to prompt customers to buy a more recent model of their phone.  And I have an iPhone 6s – relatively old.  I believe Apple are offering battery replacements this year for just $30 in response to the news, so I thought about making an appointment at the “genius bar” at the local Apple store to get a replacement.  But I don’t think I have a problem with my battery – I didn’t notice any particular issues with my battery before last week, and the settings on my phone seem to suggest that the battery is in relatively good health.  Which means that it is likely due to the software update.  And a quick internet search reveals that I am far from the only person seemingly suffering from this problem.  It appears that Apple have not done particularly good user testing on this new software update, resulting in lots of people suffering this issue of the battery quickly getting used up.  Apparently there are workarounds, but nothing simple – I’m trying to change a few settings, but not sure how much real difference that is going to make.  Instead, I’m more or less stuck with it until Apple release an update to their software hopefully fixing this issue.  My advice, hold off on updating to iOS 11.4 on your iPhone if you can.