Application Catalog :

Application Catalog : This often-requested and long-awaited feature is finally here! Configuration Manager 2012 allows administrators an option to publish deployments into a web-based Application Catalog. The Application Catalog web page is accessible to any user and is filtered to list only deployments specifically  targeted to the given users. Through the catalog, users are able to request available software that is of interest. Entries in the Application Catalog can be configured as freely available or as requiring approval. Note the Approval Requests node under Application Management in Figure 

When software is configured to require approval, the user is able to request the software, but an administrator will need to manually approve the request before deployment will continue. Administrators approve pending requests in the Approval Requests node.