Origin automatically saves each Workspace you create. This will allow you to move from project to project without losing your work.
To return to an existing Workspace, go to Scan mode and tap Workspaces. You will then see all Workspaces currently stored on your tool.
Workspaces that were created using the tape that is currently visible to Origin will appear at full brightness. You can re-open it by tapping on it.
If a workspace was created using tape that Origin can not currently see, it will be greyed out. You can still select this Workspace but will need to aim Origin at the tape you originally used for that project before it will appear.