Our App of the Day today is LinkedIn 4.0 for iPhone, iPod touch and iPad with iOS 4.0 or later.

The new LinkedIn app for the iPhone is not an update, but a complete rewrite. It's bring speed and simplicity improvements, access to your groups and the new LinkedIn Today feature. If you are a LinkedIn fan, you'll want to get this latest version for sure.

Get on-the-go access to your professional network with LinkedIn for iPhone. Find and connect with more than 120M members worldwide, read the latest industry news, keep up-to-date with your groups, and share content with your network from anywhere.

The latest version of the app includes the following changes:

What's New in Version 4.0

Brand new app completely rewritten for speed and simplicity.

Get access to your LinkedIn Groups anywhere, anytime.

Stay up-to-date with your network and read professional news from LinkedIn Today.