Apple's Passbook: 3-Month Checkup

(Image: Bloomberg News)

What Is Passbook? What Is Passbook?

Passbook allows bar code-based gift cards, event tickets and other items to display on the phone's lock screen based on the time or location they're needed. (Image: ThinkStock)

Slow Support Slow Support

There were a few supporters of Passbook at its launch but Apple wasn't one of them. Apple waited until November to add Passbook-supported e-gift cards to its own mobile shopping app. (Image: Bloomberg News)

Caffeine Kick Caffeine Kick

Starbucks was also a somewhat late addition to the Passbook wallet. Though Starbucks is a mobile-pay pioneer, it waited until October to switch on Passbook support for its mobile app.(Image: Bloomberg News)

Taking the Express Taking the Express

American Express didn't waste any time. The company unveiled a Passbook-compatible app in September, the same month Passbook launched. (Image: Bloomberg News)

Rivals? Rivals?

Square and Lemon seem to offer competing products, but they've finally joined the Passbook party. Lemon updated its wallet app to support Passbook on Dec. 8, and Square updated its Square Register app for Passbook support on Dec. 9. Pictured: Square's Jack Dorsey (Image: Bloomberg News)

Guarded Approach Guarded Approach

BillGuard offers a version of its anti-fraud service to Passbook users. It also supports the Lemon wallet, which runs on Apple devices and which BillGuard says is a "more robust" app. (Image: ThinkStock)

Kicking Off Kicking Off

The mobile rewards provider shopkick doesn't do payments directly, but rather partners with retailers such as Macy's to reward shoppers the moment they enter a store. In December, shopkick added Passbook support for mobile rewards redemption. (Image: Bloomberg News)

Sales Potential Sales Potential

The independent sales organization Merchant Warehouse said in September it would allow its merchant clients to accept payments from Passbook apps. (Image: ThinkStock)

Not Invited Not Invited

Looking for more full-featured payment apps like Isis or Google Wallet? Those don't run on iPhones, so there's no way to put them in Passbook.(Image: Bloomberg News)

Apple introduced its Passbook app a wallet that stores other mobile wallets alongside the iPhone 5 in September. Three months later, has Passbook revolutionized mobile payments? Or is it starving from lack of support?