If you are using the open source mobile framework PhoneGap to develop mobile applications, you may run into a problem first running it on the newly released XCode 4.0 development tool.
When you try to go through the Phonegap Tutorial, you will notice that on Step 4 there is no such folder called “www”.
To fix this issue, simply right click on the project itself and click “show in finder” -> there you will see the “WWW” folder along with index.html. Now drag this folder into the XCode project and voila, www is present.