You can use an Apple Gift Card (the modern "all-in-one" card) to buy both physical products and digital content, including music and apps. However, if you specifically have an older, dedicated (usually a solid gray, white, silver, or gold color), you cannot directly use it to buy digital content or "iTunes" cards through standard online checkout. Key Limitations
Depending on which card you have, you can convert its value into usable credit for apps and music: buy itunes card with apple store gift card
If you have the older physical-only card and want to use it for digital items: You can use an Apple Gift Card (the
All gift cards must be redeemed in the same country or region where they were purchased. How to Use Your Funds including music and apps. However