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iOS 8 on my iPhone 5 has been great. Haven't noticed any change in battery life. Maybe a few stutters here and there but they're very rare and inconsequential.

I'm curious about iOS 8.02, because the red 1 on the settings icon annoys me a bit, but I don't want to have all those wifi issues or whatever people are going on about just for the sake of getting rid of it.
 
To be honest, iOS 8.0.2 has been the worst for me in a while. Didn't have any major problems that most people have had since iOS 4 to iOS 7.1.2 but I've definitely been noticing a lot more app crashes, restarts, sluggishness and I'm rocking the latest phone. Kinda disappointing...:(
 
I hate it on my iPhone 5. I wish I'd never updated. Granted, my phone is eligible for the battery replacement program, and I haven't had it fixed yet (no Apple store nearby), but it never had serious issues before getting iOS 8. My main irritation is when trying to exit an app, most of the time it goes to the app switcher instead of back to the home screen. It usually takes three to five pushes of the home button to exit properly. The lock screen is very sluggish to wake up with an incoming call, or when plugged in or unplugged. Scrolling through photos is laggy and stuttering.

It's overall a frustrating experience to use my phone now, when it used to be effortless, as it should be. I haven't even had it two years yet. Lesson learned, though. When I do upgrade to the 6 or 6+, I won't be so eager to update.
 
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