PPeelen

This plugin lets you add your app’s position on the appstore to your blog. Simple add the Apple ID, select genre and range and your on the go.

Itunes AppStore App Ranking

This plugin lets you add your app's position on the appstore to your blog. Simple add the Apple ID, select genre and range and your on the go.

mjar81

This is a simple WordPress plugin that you can modify to fit your own needs. Use your iOS’s application id and it will spit out some basic HTML that you can then apply your own styling to.
Why?
I wanted to make sure that I had accurate descriptions and current pricing information for all my apps wherever I display this data on my personal websites. This was the natural thing to do.
Check out the example of what it produces here: http://www.mohawkapps.com/checkout-helper/
<h3>Advanced Usage</h3>
You can also use the following shortcodes to pull only parts of the application’s data. Please note that you must also pass the id to these shortcodes as well of the plugin won’t know what application you want the data for.
<ul>
<li>name</li>
<li>icon</li>
<li>icon_url</li>
<li>version</li>
<li>price</li>
<li>release_notes</li>
<li>description</li>
<li>rating</li>
<li>iphoness</li>
<li>ipadss</li>
<li>itunes_link</li>
</ul>
This plugin will cache the data from your application in the WordPress database for 24 hours. Application icons and screenshots are cached on your server by default but if you’d like to pull those images directly from Apple’s CDN servers (usually faster), change the value of IOS_APP_PAGE_CACHE_IMAGES to false

App Display Page

Adds a shortcode to display information about iOS apps from Apple's App Store.

Itunes AppStore App Ranking vs App Display Page