Original post by: Alex ,
At this stage iOS 11 is extremely unstable. Apple has recommended installing the Beta on an alternative device. Currently running 11 on my iPhone 7 and it is extremely unstable, almost to the point that I want to uninstall. My apps crash everyday, messages freezes almost every time I use it. Unfortunately, that's the downside of an early beta. Keep in mind that iOS 11 is being developed for the newest iPhone with the latest processor, granted we're running versions optimized for our devices. Certainly would not hurt to test your battery especially if you're still having issues after the official release.