I have an Apple gift certificate with a balance on it. I would like to use some of that balance to purchase an app from the App Store, but I don't want to fully redeem the gift certificate for iTunes credit (so I could, for example, use the gift certificate in an Apple store for actual physical products in the future). Is there any way to do this?
There are two different types of Apple gift cards. iTunes cards can only be redeemed on iTunes, and conversely, Apple gift cards can only be redeemed at an Apple Store, the online Apple Store, or 1-800-MY-APPLE. What you are asking is not possible since Apple gift cards cannot be redeemed for apps. (Or if you have an iTunes gift card, it cannot be redeemed for physical goods.)