Simple Poll - The easiest way to create polls in Slack
Cast Your Vote - Cast Your Vote is an app that allows you to set polls and a voting system and know the answer to your question.
GitHub Polls - Polls for GitHub issues and readme
My Vote - My vote is an app that allows you to create ranking, ratings, polling contests, and view the results either after voting closes or in real-time.
minipoll - Create simple shareable polls in seconds
Right2Vote - Right2Vote is an e-voting app that lets you create and manage polls or election campaigns.