Go to https://ssl.scandit.com/dashboard/sdk/projects (login required) and click on "Add a project", then select "Web App". Finally set a name for the project and a domain name to your license key.
How to get my domain name?
The domain name is the part of the URL that lies after the https:// and before the path. For example, if the URL your scanner lies in is https://www.example.com/scanner, you will want to create a license key for the domain name www.example.com.
Careful: domain names are case-sensitive and can sometimes have a different prefix that www.