This is only happening on my 7+, didn't happen on my 6s and doesn't happen on my iPad. I have a few apps (DirecTV Now and Weight Watchers) where I have to login almost daily. Sometimes I can shut down the app and relaunch and I'll be logged in, but more often than not I have to log in as though I've never used the app before. Anyone else seeing this? And yes, I've uninstalled and reinstalled the apps.