Passbook is a new Apple iOS 6 feature that lets you keep tickets, gift cards, coupons, and loyalty cards on your phone for easy access. The feature is officially only supported in iOS 6. However, a new Android app allows Passbook passes to be used on Android devices.
With PassWallet, you can download and add Passbook PKPass files to your Android device from e-mail attachments or Web links. Since Passbook is an iOS feature, you're not likely to find Android apps with integrated passes, like you would in iOS 6.
When you select a live pass, the front is displayed and tapping on it will enlarge the bar code or QR code for improved scanning. To flip to the back of the pass, go to Menu > Flip.
That's it. PassWallet is clearly not as feature-rich as Passbook on iOS 6, but it's still a convenient way to use Passbook passes on Android, at least for as long as Apple will allow it.