Performance

4.0 was really fast on iPhone 4. It was painfully slow on iPhone 3G. The difference was so , I even started to wonder if Apple was purposely driving upgrades. Now that 4.1 is out for developers, I can put my paranoid suspicions to rest- 4.1 the former glory of iOS 3 to older 3G handsets and then some. The UI is snappier than ever, gone are the random graphical glitches, and apps load quite a bit faster. As for iPhone 4, iOS is smooth, responsive, and stable- performance has improved ever-so slightly, but any enhancement in that area is always welcome.

HDR

This one sort of came out of left field but is an to iPhone 4's already terrific camera. In some quick home tests, I've already seen that HDR photos generally look better than non-HDR ones. Obviously the results really shine when there is a lot of light and a lot of shadow in the frame, but I'd say roughly 7 times out of 10, turning HDR on improves picture quality. The only downside is it takes a couple extra seconds to take the photo (as it's actually taking three photos in rapid succession), but this is a very minor gripe.

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