Is Xcode 4 required to continue iPhone development?
It has been a while since I've last done programming XCode for the iPhone and I have noticed that there is a new version of XCode, XCode 4, that seems to only be available for the Lion OSX according to this link https://developer.apple.com/xcode/.

I have heard from a friend that Lion has caused a lot of havoc in the app space so I was wondering if there were any compatibility issues with developing apps using an older version of Xcode.

I currently am running on Snow Leopard OSX ver 10.6.8 and am using Xcode 3.2.3. Is this setup still capable of creating fully functional applications or is an update/upgrade required?

Any and all extra information pertaining to this matter would be greatly appreciated as well.
Is Xcode 4 required to continue iPhone development?
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It has been a while since I've last done programming XCode for the iPhone and I have noticed that there is a new version of XCode, XCode 4, that seems to only be available for the Lion OSX according to this link https://developer.apple.com/xcode/.

I have heard from a friend that Lion has caused a lot of havoc in the app space so I was wondering if there were any compatibility issues with developing apps using an older version of Xcode.

I currently am running on Snow Leopard OSX ver 10.6.8 and am using Xcode 3.2.3. Is this setup still capable of creating fully functional applications or is an update/upgrade required?

Any and all extra information pertaining to this matter would be greatly appreciated as well.