An owner can invite someone to be a contributor to their desktop. The owner still owns and controls that desktop, they are just granting the privilege to someone else of being able to add, edit, and organize content on the owner's desktop. An owner can have as many contributors as they would like.
IMPORTANT - Before you can make a follower a contributor, you need to have at least 1 file on your desktop. Upload an image or a doc file to establish permissions on your google drive folder to allow others to become a contributor to that desktop. If you see followers in your desktop that only have the option to block them, you will need to add a file to your desktop first. Once you do that, you will be able to make a follower a contributor (unlocking the ability for them to upload files to your desktop).
If the desktop is private, you need to invite the person using the email of their current middlespot account to become a follower. Once the person has accepted and become a follower, they will appear in the follower menu of the desktop.
To become a contributor, you must already be a follower of this desktop.
The owner can then tap the Contributor radio button in the followers name. It will automatically move them to become a contributor.
The desktop will now show up in the person's DESKTOPS folder under Contributing tab.
They will receive updates when changes are made on the desktop.