When you're creating or editing a listing for an app, the Offering tab asks whether you want to offer a free trial of Salesforce and your application. The free trial is a non-production Salesforce organization that includes your app and sample data. If a customer chooses to purchase the app instead of letting the trial expire, the organization becomes a production version. We recommend giving customers the option to remove sample data by writing a data cleanup script and including a button in your app.
You can also choose to offer a test drive, which is a single read-only version of your app that all customers taking the test drive log into. Like free trials, test drives are Developer edition organizations that include sample data and whatever configuration you choose.