As I write this I'm upgrading my wife's iPhone 3G to iOS 4, so I'm probably going to end up sleeping in the shed tonight: upgrading my 3G rendered it unusable, and while a factory reset seems to have improved things it's still pretty slow. I want the new features, but it looks like I have to suffer a slower phone in order to have them.

I'm not the only one: when we asked iPhone owners for their update experiences yesterday, 3GS owners were generally happy and 3G owners were hurling themselves off buildings.

The comments aren't from Apple haters - "Apps take longer to open, but I do like the combined Mail box," Steveager writes - but there are plenty of people growing beards as they wait for apps to open.

"Wish I'd never upgraded," Dank says. "Definitely slower," says Robw. "Loading SMS messages and maps is a real pain."

Luisasolarf found the same on an unlocked, jailbroken 3G: "After the upgrade it turns out to be very, very slow. Some apps take a long while to load - like 10-20 seconds - and often the control becomes unresponsive." "It doesn't feel slower, it IS slower," says Mymeltingbrain, while Nathanshane says "I want to downgrade ASAP".

Not everyone is having problems, and in my own case most of the really big issues went away with a factory reset - but there's clearly something going on here, and my money's on lack of horsepower.

Apple disabled key iOS 4 features on the 3G - background wallpapers and multitasking - because it didn't have enough RAM, and says "not all features are compatible with all devices". Maybe all those new goodies in the OS - the folders, the spell checker, the new APIs - are too ambitious for the 3G, or maybe there's a leaky app somewhere causing chaos, but 3Gs seem to be encountering problems that aren't affecting the 3GS.

There's a business cliché, "under promise and over deliver": it means delighting customers by being better than they expect you to be. For some 3G owners, iOS 4 appears to be doing the very opposite.

It's a no-win situation for Apple: give us iOS 4 on handsets that can't cope with it and we'll moan; declare that "3Gs are rubbish! No iOS 4 for you!" and we'd be moaning about that instead.

And of course, as Apple fans we always want the very latest Apple stuff - which is why I'm going to end up spending tonight in the shed.

I know this update's probably going to ruin my wife's iPhone, but hey! New Apple thing! New Apple thing! New Apple thing!

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Liked this? Then check out Hands on: iPhone 4 review

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