Allow people in Slack to "clip" messages and save in a 3rd party system using a message actions and a Dialog.
Allow people to post announcements to a restricted channel from time to time, with admin approval.
Allow people in Slack to create a helpdesk ticket in a 3rd party system using a Slash Command and a Dialog.
Learn how to create the App Home view and use the modals
Learn how to design an expense reporting app using home tabs, modals, and messages.