As time passes by here in the UK, Passbook support continues to grow. This time up it's the turn of Subway, with an update to their Subcard app that allows you to finally add your card to Passbook on your iPhone. Your Subcard ID and recent transactions can now be accessed from your Passbook wallet.

That's all that has been added, but to see such apps integrating Passbook is welcome news. Particularly here in the UK, Passbook enabled apps have been slow to take off, but in recent weeks we've seen two of the country's biggest Airlines add support, and Apple themselves have added Passbook to their iTunes Festival application. This also follows the news that Starbucks is the largest use case in the U.S. of mobile wallet apps, another Passbook integrated application. What do you guys have in your Passbook? Mine is a little slim, with only the Subcard and Starbucks card in there at the moment, how about you?