Ever since Apple introduced multitasking with iOS 4, some iOS users have been under the impression that quitting idle apps helps save battery life and increase performance. I’ve always been skeptical of this claim, and it turns out that my skepticism was right.
Former Apple Genius Bar tech Scotty Loveless explained on his blog that closing apps and then reopening them as needed actually worsens your iPhone’s battery life. This is because all closing apps does is remove them from your iPhone’s RAM, so when you reopen them, your iPhone needs to reallocate space in your memory and must use additional resources to do so, hence worsening your battery life.
It’s also worth noting that, according to Loveless, your iPhone and iPad will automatically close apps when it needs more memory, so there’s no need to interfere with this process. The only time an app can actually be running in the background is if Background App Refresh is enabled or if an app is playing music, recording audio, grabbing location info or checking for VOIP calls.
Let your iPhone do the busy work, folks.