Want to buy a new song or video from iTunes even though you’re offline? A new Apple patent envisions a way, at least sometime down the road. Granted to Apple today by the U.S. Patent and Trademark office, the patent appropriately named “On-device offline purchases using credits” describes a system of using credits to purchase iTunes content that’s stored on your device but which you don’t already own. The goal is to allow you to unlock and play iTunes songs, videos, and other items without having to be online. You would first buy credits that you can apply to future offline iTunes purchases. You’d also have a library of items on your mobile device that you don’t actually own but may wish to purchase. These items could include recommendations from iTunes that were downloaded the last time you were online.