"Background" battery usage for the Facebook and Twitter apps is still a problem. For instance, I just checked the Last 24 Hours battery usage on my iPhone 6S and Facebook accounts for 8% -- 26 minutes on screen, 32 minutes background. Something just isn't right there.
Edit: Background App Refresh is disabled for the Facebook app
I'm still trying to cement the habit of closing the apps out from the multi task screen when I'm done using them. Apparently I haven't been very good at it over the past 24 hours.