Recently, my iPhone 5 started bogging down in an epic way–it would take forever to launch apps, often stalling out entirely and requiring multiple tries to even get apps to launch. I tried restarting, shutting down other apps, etc. and nothing worked.
I started seriously wondering whether this was an evil plan that Apple had slipped into later versions of iOS 8 to punish folks who’d declined to drop a couple hundred bucks to upgrade to an iPhone 6.
As it turns out, the culprit was a newish setting under Settings > General called “Background App Refresh”. The purpose of this setting is to allow apps to pull down new content when you’re on a wi-fi network, and is no doubt a lovely thing on some level. But, between Dropbox, Chrome, FaceBook, Instagram, Mailbox, Messenger, and a dozen other apps, it was murdering my phone.
I turned it off, and my phone was instantly back to normal. You can control this setting on an individual app level, so perhaps later I’ll experiment with turning off various apps to figure out the biggest culprits. But for now, I’m just happy to have a reasonably working phone again.