Error while installing the Festival App (Solution) Package

When I am trying to install the Festival App (Solution) Package, I am getting the following error message.

Install failed. 
Custom Apps Limit Exceeded. You've exceeded the maximum number of custom apps allowed in your organization. (Required: 1, Available: 0). To learn about options for increasing the custom app limit, please contact an administrator or salesforce.com. Please help.

Start by checking your system resources to see if you have exceeded any limits.

1) Click on your Name in the upper-right corner of the screen
2) Click on Setup in the drop-down list
3) Click on System Overview in the left navigation bar
4) Review the various limits and how many resources you have already used.
5) If you are at or close to the limit for resources you may need to delete some to finish installing the (Solution) package.