Add an existing framework in Xcode 4

Steps to add an existing framework in Xcode 4:

1. Click the project in the project navigator.

2. In the project editor, click a target.

3. Select 'Build Phases' tab

4. Expand 'Link Binary With Libraries'

5. Click '+' button to add a framework.

6. Go back to the project navigator, you will see the new framework. You can drag it to 'Frameworks' group.