A method and apparatus for reputation scoring of applications on social networking services is described. A reputation score system scans a profile area of an application operating in a social networking service and generates a profile metric based on the content of the profile area. A reputation score system scans analyzes application installation behavior of an application and generates an installation metric. The reputation score system analyzes application activity of the application and generating an application metric. The reputation score system analyzes permissions requested by the application and generates a permissions metric. The reputation score system generates a reputation based on the profile metric, installation metric, application metric and permissions metric.