Hi, I have a iPhone 6 64gb version and want to know if iOS 11 will be slower than 10 on my phone. I'm seriously happy with 10. My fear is I'm going to experience a huge slowdown of system response (opening apps and working with them) and make my phone impossible to use. Thoughts? Anyone try iOS 11 on iPhone 6?
You'll definitely see a marked drop off in the time taken to open some apps. The iPhone 6 has 1GB of RAM, and iOS 11 will inevitably use more RAM in general use than 10. Less available RAM means more time spent shuffling things around, or applying compression.
Once an app is launched, you'll not likely see a huge difference. I have a iPad Mini 2, and an iPad Pro 12 both running the beta. The mini is a generation behind the iPhone 6, but also has 1GB or RAM. It's pretty painful, and I wouldn't want it as a daily driver. The Pro by contrast doesn't feel noticeably different in real use.
I don't think iOS 11 will be the end of the line for the 6, and if you hold out for 11.1 or 11.2 things will be better yet, but I think it's pretty clear that iOS 12 will run like a dog on anything with 1GB or less, so this will likely be the last update you'll want to do IMHO.