A:Answer This is impossible to say, because it depends on what you're planning to use it for. For example, an Apple Music subscription is 9.99/month, so $100 will last you nearly a year (once you figure in taxes, etc) if you use it for nothing else. Cloud storage options are also paid monthly and there are also plenty of opportunities to buy/rent movies, purchase music, in-app purchases for games. It's really nothing so much as like having $100 available to buy a wide variety of products, and it just depends on how much you purchase, how often, and how expensive it is. I have Apple Music, and Cloud Storage, and purchase the occasional in-app content, so for me, $100 would probably last me about four or five months. Your own milage will vary based on your needs or wants.
The good news is that the funds never expire. So as long as you don't spend it all, the money remains in your iTunes account indefinitely.
TL;DR--It depends on how fast you spend it!
