You might not know it, but Amazon sells coins that can be used to purchase apps and games from the Amazon Appstore, or they can be applied toward in-app purchases in Appstore apps that support them. Why buy coins instead of just using your credit card to pay? The answer is simple: Amazon coins can be bought at a discount, so you’ll never pay full price for an app as long as you’re using coins.

The typical discount on Amazon coins is up to 10%, but for a limited time Amazon is doubling that discount to 20% on two of its most popular coin bundles.

100 Amazon coins are worth $1, and Amazon sells five different bundles: 500, 1,000, 2,500, 5,000 and 10,000 coins. The two largest bundles are Amazon’s most popular ones, and they have a value of $50 and $100, respectively. From now through November 1, however, you can buy a 5,000 coin bundle for $40 and 10,000 coins will cost you just $80.

Amazon Coin sale (5,000 and 10,000 coin bundles)