Saving Your Battery in iOS 11
Like many people, I noticed a decrease in battery life after I installed iOS 11 on my iPhone.
This is actually a very common problem on all iOS versions. However it does seem that each new version of iOS brings complaints about faster battery drain. Some say it’s because you’re using the phone more as you explore all the new features and updates. I have also heard the argument that the new OS is doing a bunch of rewriting or caching or something, and that battery life will even out after the first couple days.
With iOS 11, however, there may be another culprit.
If you’ve ever searched for tips on prolonging iPhone battery life, you’ve almost certainly encountered this one: turn off email fetch. The reasoning is that battery life suffers if your phone automatically checks for new mail every 15 or 30 minutes.
That’s why I always kept my accounts set to “manual,” as I prefer to retrieve mail when I want to retrieve mail.
However, after installing iOS 11, I noticed there were frequently new messages waiting for me each time I opened the Mail app. So I checked my email account settings (which, incidentally, are no longer found in Settings > Mail and, sure enough, all my accounts had been set to Fetch!
Needless to say, you are better off disabling Fetch. Here’s how: tap Settings > Accounts & Passwords > Fetch New Data and change it to Manually. You can also change this to check for email hourly, every 30 minutes or every 15 minutes. Try one of these if you iPhone battery is suffering.