The best iPad apps of the week, all listed in one place.

The Google Books iOS app (which was removed from the App Store due to in-app purchasing issues, and then reappeared soon after) has recently received an update. Now, the e-book reading application allows users to manage the contents of their digital library, and the formatting of e-books is much improved. Furthermore, the latest version of Google Books also boasts new accessibility features.

An update for WhatsApp Messenger is now available to download in the App Store.

An update to Trainyard recently arrived in the App Store, adding iPad support, Game Center integration and new content. The application is a fun puzzle app (and something we've reviewed before). Currently, it's available to download in the App Store for just $0.99.

A recent update to Parallels Mobile has made several changes to the application, including improving the app's performance and stability. Furthermore, the universal application is now available to download for just $4.99 (for a limited time only).

The popular Growl client for iPhone, Prowl, has recently received a major update adding iPad support, a new design, offline access to notifications and much, much more.

The popular "virtual file cabinet" for iPhone, Keychain, has recently received an update. Now, the latest version of the application (1.1) includes a variety of new features, bug fixes and improvements.

The popular Twitter client for iPhone, Tweetbot, has recently received an update. Now, the application features support for Tweetmarker, and various improvements and bug fixes.

Elements, one of the first apps to bring Dropbox text editing to the iPad, and now one of the most popular, just got an amazing update.

Great news, social networking fans: The popular iPad app, MyPad, has recently received a major update, adding new features and a variety of all-important bug fixes. Among the changes are a Twitter timeline feature, the ability to close windows with a gesture and a new photo slideshow.

Updates, updates, updates. We see them pop up all the time. In fact, as I write this I have four available, and Pocket God is one of them. I don't really keep track of the numerous updates (though AppAdvice does), but I’m guessing Pocket God probably has more than any other app, clocking in at number 40 with an episode called, Battle of the Gods.

The popular zombie-smashing app Zombieville USA has recently received an update, adding support for the Retina display and iPad compatibility. Furthermore, the app's developer has announced that a sequel to the game - called "Zombieville 2" - is coming this summer.

That's right, PopCap Games recently released that all-important update for Plants vs. Zombies. Now, iPhone 4 and fourth generation iPod touch owners can enjoy playing the application in high definition, on their Retina display equipped iOS devices. Furthermore, the app has received a series of performance improvements, making it more stable than ever before.

The popular iPad application, Zinio Magazine Newsstand & Reader, has recently received an update. Now, users of the application can purchase magazines in-app and enjoy article previews. Furthermore, the app has received significant performance improvements, meaning it's now faster and more stable than ever before.

The popular Instagram iPhone app has recently received a minor update, improving social network sign-ins and the application's performance.

The popular Yahoo! iPhone app has recently received an update, changing the application's interface and adding a variety of features, including media galleries and an offline mode for Yahoo! News articles.

The popular, free application for Apple's second generation iPad, Evernote Peek, has recently received an update. Now, users of the app can enjoy hearing audio clues, and interacting with study notebooks that have been shared with others.

Great news, Netflix fans: The popular iOS application, which allows users to access their Netflix account and stream videos on-the-go, has recently been updated. Now, the app supports Apple's most recent software updates (iOS 4.3.4 and iOS 4.2.9) and the beta versions of iOS 5. Obviously, this is great news for Apple fans and iOS developers alike.

Moments ago, Amazon updated its Kindle iOS application, making a variety of changes. First, Amazon removed the Kindle Store from the app, falling in-line with Apple's in-app policy (which the company appears to be enforcing now). Second, the Kindle app now supports newspapers and magazines (which obviously have to be purchased outside of the application). And third, users of the application can now share quotations from texts with friends, via Facebook and Twitter.

The Facebook iPhone app has recently received an update (version 3.4.4), and though a variety of minor changes have been made, the application is still not compatible with Apple's iPad.

The popular Final Draft reader for iPad, FDX Reader, has recently received an update. Now, the application is a universal app, meaning it's compatible with the iPhone, iPad and iPod touch. Furthermore, the app has received a price-drop, and is now available to download for just $4.99.

The popular iOS application StumbleUpon! has recently received an update. Now, the application looks much better on the iPad, and the app is also improved when running on the iPhone, too.