Here is some info I come across, it's a life saver!! Thanks to JLR
Just recently I got a hold of an iphone 3g so it was time to upgrade from my original 2g phone. Hereís the problem though, my 2g was jailbroken and I had the Categories App installed. Hereís an important note for anybody that hasnít gotten from a jailbroken iPhone to a non-jailbroken iPhone: make sure to remove your categories and place your apps back on the main Springboard before updating your iPhone.
If you donít, the icons for those apps that were in your categories will remain hidden after you update the iPhone. So although you have the apps installed, they wonít show up and you canít access them. So yes, I made that mistake, I updated without removing my categories.
Thereís a couple of solutions Iíve foundÖ one is to re-jailbreak the iPhone, install SBSettings and unhide the icons through SBSettings.
What if Cydia was in a category?
This was my next dilemma; I had Cydia within a category so when I re-jailbreaked my iPhone, I didnít have access to Cydia to install SBSettings. But luckily there was an option other than having to restore the phone and start from scratch.
iPhone General RestrictionsThereís a simple solution which doesnít involve jailbreaking; you can Enable Restrictions in Settings->General->Restrictions, go back to the main screen, then go back in and disable the restrictions. This will reset the file that determines which icons are shown and which are not. This is what finally gave me my icons back without having access to the apps in Cydia.
Iíve been getting lots of hits on this article recently, no doubt because of the iPhone 3.0 release. Anyhow, a common question asked which I did some research for:
What if Settings was in a category?
Youíre going to need the following software:
iPhoneBrowser - Lets you browse the directory structure of your iPhone
Once you have that installed, connect your Iphone to your computer and launch iPhone Browser:
1. Using iPhone Browser go to:
2. Find the file: com.apple.SpringBoard.plist
3. Delete that file
4. Restart iPhone
iPhoneBrowser is also a good tool to retrieve saved videos from Cycorder and take a peek under the hood of your iPhone. Beware though, this is all at your own risk.