Zotero allows you to collaborate with fellow researchers by sharing your citations either publicly or privately. You can also control the level of access members of your group have by assigning read only or write authorizations.
To create a new group select the Group icon in the Standalone App.
You will then be asked to log in to your online Zotero account. From here you can create your group by choosing a group name and selecting which type of group you would like to create.
Once you create the group you will be given the opportunity to further assign rights to the group, such as read only or editing rights.
To add members to the group you will need to click on the Groups tab at the top of the page. This will show you what groups you have available to you and if there are any outstanding group invitations. To add members click on the Manage Members link.
From here click on the Send More Invitations link.
Enter the email address of the person you would like to share these citations with, they must also have a Zotero account. To add multiple email addresses list addresses separated by a comma, i.e. email@example.com, firstname.lastname@example.org.
You can also add a message to the email so your invitees know why they're getting this invite.
Beyond citation management, Zotero offers some additional resources.
The Zotero Timeline allows you to view your cited resources by chronology. The Timeline can be found under the Tools option in the Standalone App menu.