SendLater - Email scheduler for Mac Mail.
Trello for Slack - Organize anything with anyone, inside Slack
Shortwave - Email smarter & faster with a reinvented experience for your Gmail
Actions from Slack - Turn Slack messages into tickets, issues, tasks, and more.
Assistant.to - GoToMeeting. Put your GoToMeeting link in the Assistant. to "Location" field. Once the recipient selects a time, you will both receive an invite with a unique GoToMeeting link.
Slack Jira Integration - Easily keep issues moving right from Slack