As if to facilitate the purchasing of its new line of MacBooks, Apple has just updated its Apple Store app with a couple of new features.

Apple Store is the official mobile client for the tech giant’s online store. It makes for convenient browsing and buying of Apple’s popular products with an interface that’s optimized for the iPhone and iPod touch’s screen.

It has a feature that is all its own in the form of EasyPay, a scan-and-pay tool that you can use in buying accessories in a bricks-and-mortar Apple Store. But it mostly inherits its parent Web site’s key features, including custom iPad engraving and Mac configuration.

Apple Store 2.2 introduces Express Checkout.

The 2.2 update for the Apple Store app adds another feature that’s a carryover from the main online store. Dubbed Express Checkout, this feature delivers exactly what it says on the tin. Once Express Checkout is enabled, the app lets you quickly purchase items by tapping the buy button and entering your Apple ID password. Your order will then be processed using the payment and shipping settings you specified upon signup.

The other new feature introduced by the update is a location-based one and is accessible on iPhone 4S only. If you intend to pick up an order at a particular Apple Store, the app can notify the specialists at that branch so that they can pull out your purchased products beforehand. By the time you arrive, your order is ready to be taken home. Now that’s express checkout.

Apple Store for iPhone and iPod touch is available in the App Store for free. Will you be using this app and either of its two new features in buying a new MacBook Pro with Retina display?