Investors are widely expecting Apple (NASDAQ:AAPL) to get into the mobile payments game sooner or later, especially after CEO Tim Cook mentioned that the company now has 575 million active iTunes accounts with credit card information just a click or tap away. That makes its active user base nearly three times that of, the largest e-commerce company in the world.


Passbook in iOS 6. Source: Apple.

Apple's stepping stone until then is Passbook, which aggregates other wallet-related items like gift cards, loyalty cards, and more. Even though Passbook doesn't offer any type of uniform payment method that links to a credit card, the app is already taking off in popularity among retailers and merchants.

GigaOM recently spoke with CashStar marketing exec Gene Cornfield about Passbook's potential. CashStar helps many well-known retailers create digital gift cards, so it has valuable insight into how Passbook is progressing. The company says that approximately 33% of gift cards that are sent are opened on a smartphone, and 66% of these smartphones run iOS 6. Roughly 30% of these gift cards are subsequently added to Passbook.

Cornfield told GigaOM that many retailers were skeptical at first, but eventually warmed up to the idea as users began to understand its value proposition. Using gift cards is currently the best way for users to spend money at retailers, with CashStar saying "millions of dollars" have been processed through Passbook.

The location-based reminders also help users remember to redeem cards once they are near a store. Companies only recognize gift card dollars as revenue once the funds are spent. Reloadable store-specific cards are also helping retailers make payments. I use the Starbucks card in my Passbook all the time to buy coffee, which reloads automatically.

Apple gave no hints of a payments service at WWDC earlier this month, but considering Passbook's early success, this is an important opportunity for the Mac maker. Like most of its services, payments will likely generate negligible operating income and instead will be positioned as a complementary offering that spurs device sales.

Google Wallet has mostly failed to make a dent in the payments market, leaving a wide opening for Apple.

Fool contributor Evan Niu, CFA, owns shares of Apple and Starbucks. The Motley Fool recommends, Apple, Google, and Starbucks. The Motley Fool owns shares of, Apple, Google, and Starbucks. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.