No, at this time there is no limit to how many users you can create on app.raven.com and there is no limit to how many users can be signed into the Raven Scanner to utilize the 'Switch Users' feature.
To learn how to create a user on an already existing Raven Cloud Account click here.
To lean what roles you can assign a user click here.
Please contact support@raven.com or call 1-800-713-9009 if you have any questions.