Credit-based reading replaces a price with a currency. You buy coins, gems, keys or tickets, and each locked chapter costs a number of them. Almost every serial-fiction app works this way, and a few audio apps do too.
Why it is built like this
Three reasons, and only the first is about you. A currency hides the price: thirty coins does not feel like fifty cents. Packs never divide evenly into chapter costs, so there is always a remainder too small to spend and too annoying to waste, which pulls you toward the next pack. And a currency decouples spending from reading, so the painful decision happens once, at the shop, rather than at every chapter.
Working out what you are paying
- Find the cheapest pack price and the number of coins it contains.
- Divide: that is the price of one coin.
- Multiply by the cost of one chapter. That is the real price per chapter.
- Multiply by the number of chapters in the book, which is usually on the book's page and never on the payment screen.
Do it once for any app you are considering and the comparison with a subscription becomes obvious. Heavy readers almost always pay less on a subscription where one exists.
One rule in your favour
Tip
Coins bought through an in-app purchase on iOS cannot be made to expire. Apple's App Store Review Guidelines state that "any credits or in-game currencies purchased via in-app purchase may not expire", and that there must be a way to restore them. Coins bought on a website are governed by that service's own terms instead, which may say something different.
Free coins
Most apps hand out small amounts for waiting, watching an advert or opening the app daily. They are real, they are slow, and the rate is set so that a committed reader will still run out. Where an app documents how much free currency it gives, that is worth knowing before you start a long book.
See also cliffhanger paywall, serial fiction and the glossary.
Sources
Official pages, documentation and store listings we read for this page (last check October 27, 2026).