Ask a Dev: What's 'Tap and Pay' in Android KitKat?

A new Android KitKat feature called "tap and pay" will not only let you buy things with a wave of your smartphone, but also may let you open a hotel room, enter a stadium or even unlock your front door.

The latest video in our Ask a Dev series looks at how you can use tap and pay to better manage your electronic transactions.

The feature lets you pick your default wallet app, so when you wave your phone over a non-contact payment system, that app will handle the transaction.

The software can be used in plenty of practical ways outside of credit card replacement. Hotels can use the feature to design an app that would mimic a room key. The app would give you a code at checkin, which would save on your phone and allow you to wave it over a lock to open the door to your room. Read more...