Inc.com mobile economist John Koetsier has just taken one for the team and found a possible solution for us all, but we warn you, it's not an easy option.
John pointed out that if you go into your Settings > Battery and go to the top, you can see which of your apps have drained the most of your battery in the past 24 hours, or week.
"Shockingly, Facebook accounted for 47 percent of my battery use during the previous 24-hour period. That day, I'd posted a few times, browsed for maybe 30 minutes in four or five sessions, but otherwise left the app to its own devices."
Note that this was even while he had 'Background App Refresh' turned off.
Even Android expert Russell Holly revealed last year that deleting the Facebook app could result in battery lasting for 20% longer. Le sigh.