You can manage each application information anytime, in your dashboard. The screenshot below clarifies your applications' properties: an icon for public applications, an icon for private applications, and a list of actions delete, clone (copy) and edit information.
To edit an application information, click on the dots (vertical ellipsis) at the top right corner and choose edit. A popup will appear where you can change the name, description, icon and color of your application.
Is public: if you check this option, then the application will be visible for every user in your workspace. If you want to restrict access to the application uncheck "Is public" option. You can manage permissions of each private application with Workiom advance permissions.
Note: all applications are created public by default.