Update apps on iPhone AND iTunes?

Why do I update apps on my iPhone and then, when I sign into iTunes a few days later, I have to download all those apps into iTunes? I feel as though I'm doing the same thing twice. Which SHOULD I do? Would I end up doing the same thing if I just synced my iPhone everyday?

It sounds like that you have your apps on both your computer and the iPhone, so when a update is released it updates it on both. Your best bet to resolve this is to update it on one of the devices, then sync them together. This will update both the computer and the iPhone depending on which one downloaded.

Hope this helps!

From Apple.com on/about the iCloud:

If you own multiple iOS devices, iCloud makes sure your apps are everywhere you want them. Download a new app on your iPhone, and it automatically appears on your iPad. You don't have to worry about keeping your devices in sync because iCloud does it for you. Or say there's an app you bought way back when that you wish you had on your new iPod touch.iCloud lets you see your past downloads in one convenient place: your purchase history on the App Store. Since you've already purchased these apps, you can download them again - at no additional charge - to your iPhone, iPad, or iPod touch.1

Hope this helps a bit, Brian.