How to manage Apps without wiping out your iPhone App data? I want one to do one simple task: Manage my iPhone 4 apps using the iTunes interface on my laptop. I've done it before, but now there's a problem.

When I go to the Apps section on iTunes, the apps are all faded out and I can't get access to move Apps around. If I click on the Sync Apps button, I get this message: 

"Are you sure you want to sync Apps? All existing apps and their data on the iPhone "[iPhone name]" will be replaced with apps from this iTunes library."

I don't want to wipe my iPhone Apps, I simply want to move Apps around like I used to. I can't say I trust that this iTunes library has all of the Apps correctly. I've run a sync in the past and it deleted Apps I already had installed before.
It sounds as though your iPhone and/or iTunes aren’t synced to each other. Unfortunately, for you to manage the apps on the iPhone from iTunes, the iPhone needs to be synced to iTunes. So you’ll have to go through this procedure at least once, and replace what’s on the iPhone w/ what’s in iTunes.

No way around that, but thankfully, any apps you’ve purchased are free to you to download again, so if there are any that are missing in iTunes, just download them again.

But yes, if any of the apps aren’t in iTunes, and you’ve got data stored in those apps, that data will be lost.