When purchasing Nebula you will be given an account on the Nebula Git server. You will have to have preinstalled Android Studio, Intellij Idea(community edition is fine) and the Arduino IDE. Specific instructions for each is available on the DOCUMENTS page.
From the IDEs you will open a "new project from Git" then save the Nebula project locally. The project will run the Demo code but you are free to add, modify or delete code as needed for your own networked projects.