From the desktop application it is possible to change your current inmydata tenant by selecting the change tenant menu option on the Menu, or when logging in to the application.

If you enter an invalid user or select the Close (X) button on the top right of the screen of the screen you will be prompted by this message, select Yes to access the Change tenant screen.

In the Publisher Application the Change Tenant option is under the Tools Menu

In the Dashboard Designer the Change Teneant option is on 

The Screen to change allows you to change the tenant name, or by selecting the Advanced Option you can change the domain name.