The best Slack applications for startups include Trello, Zapier, Google Calendar, Zoom, Hubspot, BuddiesHR suite (Billy Birthday, Alfy Matching, Pulsy Survey, Clappy Kudos) among others.
A Slack application is an extension or an integration that you can install on your Slack workspace and that extends Slack's capabilities.
Reasons include: Extending Slack's capability, Improving the employee experience, Removing the need of external softwares, Enhancing productivity by finding everything in one place.
The Slack applications can be found in 2 places. First via the slack app directory available on Slack's website. Second via your Slack workspace > Bottom left of the sidebar, Click on App > Manage > Browse Apps.
Some of the best Slack integrations apps include Billy Birthday, Trello, Alfy Matching, Dropbox, Zapier, Pulsy Survey, Calendly, GitHub, Salesforce and Clappy Kudos among others.