May be sluggish/won't be able to downgrade
Apple does mention that not all options in iOS7 will be available on the older models, especially the iPhone 4. Obviously some hardware limitations will hold it back from enjoying the whole new experience of the new OS.
But what we don't want to see is a repeat of iOS 6 sluggishness with older devices. When the 3G/3Gs iPhones became very slow and unusable after the update, and it was very difficult, nearly impossible, to revert the OS to the earlier version. -Dominik Tomaszewski
Near-Windows 8-esque look
It's nowhere near the abomination that is Windows 8 with its ugly, two-dimensional user interface, absence of drop-shadow cues and sharply squared-off corners. But by losing the glassy curved-effect buttons that have been part of iOS since it was simply iPhone OS, and erring toward the sharply angular, Apple starts to look like the imitator and not the innovator. Putting a three-dimensional effect back with a moving, recessed wallpaper may help - will have to see how that works out. -Andrew Harrison
Having to queue up
When Apple announced that everyone could download iOS 7 for free on September 18 I had one sinking feeling: everyone wants to upgrade on September 18. This can be quick and easy, but it can also be like trying to buy tickets online for Glastonbury: painfully slow and frustrating as the world tries to hook up with Apple's over-loaded servers.
Previous iOS updates have bricked the device when the new iOS didn't install correctly, forcing users to restore their iPhone or iPad before trying again.
When it eventually does download it can take the iPhone or iPad another 10-20 minutes to start up. By which time your iPhone's battery will be flaking out.
Ok, so I said that I was happy that I wouldn't have to queue up in our eight things we love about iOS 7... -Simon Jary
Choosing a font for a phone is difficult: you've got to work with a typeface that's as suitable for texting 'Come party!!!' as 'Call home. Something's happened to Dad'. But Apple could have at least picked something less unimaginative than Helvetica Neue, especially as it's had to settle for even-more-corporate weights of it as newer versions of the iOS7 beta has emerged.
When iOS7 first emerged, the thin weights of Helvetica Neue seemed fresh - but it appears that these have proved difficult for users to read quickly and understand what they say, so Apple has dropped the Helvetica Neue Light for good-old, tried-and-tested Helvetica Neue (a refinement of the original Helvetica used in previous iOS versions).
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