You can create your own simple poll in Joinable on any topic, allowing your members to cast their vote. To create, go to "Inbox", then "+ Message" and select "Poll" from the options at the bottom. On this screen you can configure your poll, entering a title, plus all your voting options next to the list of circles. Once you have input these, select "Add Poll", which will save it in a message. From here, you can decide what to write in your message and who you want to send it to.

Once you have sent the poll, members will be able to vote, by clicking on their preferred option. They can change their vote at any time, by selecting another option. The poll will tally up underneath each line and by clicking on the green bar, you can see which of your members have voted.