StrawPoll - StrawPoll Meetings offers a simple interface to create polls that can be used to schedule meetings. With two simple steps, your next meeting is scheduled in seconds.
Twitter Polls - Polls embedded in tweets
Loqbooq - Decision log for your project.
Simple Poll - The easiest way to create polls in Slack
poal.me - Free, realtime, configurable, user created polls with pie charts as well.
Polls for WhatsApp - Create & share quick polls in your WhatsApp groups