If you are currently subscribing to the SalesScreen AppExchange app and want to discontinue, you'll have to uninstall the package from your Salesforce organization.
Note: If you want to completely terminate the SalesScreen-Salesforce integration, you should first terminate it from the SalesScreen interface. Follow the In SalesScreen section below.
In SalesScreen (Optional)
Sign in to SalesScreen as an administrator and navigate to Manage > Settings > Integrations > Manage Salesforce. Click on the Settings tab. Alternatively, navigate to the following link:
Finally, click on Terminate Integration and confirm your choice.
Sign in to Salesforce as an administrator and follow the steps described in the following link. The print screen image below is a quick summary of the steps you need to carry out.