Okay i had my phone in iOS 8 for a day now
iOS 8 on 16GB iPhone 4s, its my test phone for now,
Here are my thoughts,
1. Performance nearly same as iOS 7.1.1, in iphone 4s every part of the phone feels snappy, only noticable "lag" is while swiping down for spotlight search, i've seen significant improvement in smoothness when opening up control center, previously on 7.1 it lagged , multitasking is super fast now.
has
2. Nothing have changed in the ui, status bar in lockscreen appears slightly smaller, a new health app
3. control center changed a bit, maybe its the new brightness icons, new animation to the background when you adjust the brightness
4. New animation when you swipe down for spotlight, the background blurs up now. It is a little laggy though.
5. Lots of new stuffs in the settings, usage for battery now individually displays battery usage according to apps, Siri has voice activation when plugged in, lots of new stuffs in accessibility like grayscale, nothing removed..
6. Appstore have changed, i guess it might be the color, and some ui changes, nothing major.
8. New keyboard, it predicts what your next word might be, like if you type I , the suggestions will be like "have, am, had" , i turned it off it gets a little annoying just like autocorrect.
there are much more improvements/ changes but these are the ones i've noticed so far, it is very very very buggy for now, everything crashes, especially downloaded apps, its expected as its just beta 1 so lets see whats to come in the next beta