Slido is a cloud based audience engagement tool particularly geared towards live events. The platform can host questions asked by users in a Twitter-esque approach, produce surveys, run quizzes and collect free text information (known as "ideas") from the audience and display and switch between these in real time seamlessly as the presenter specifies.
The guest and admin platforms can be found at slido.com (or http://www.sli.do) or guests can also download the app for free on iOS/iPadOS and Android through the Apple App Store or Google Play.
Event organizers can sign up for a free account which is limited to one type of poll/quiz type at a time and questions with no moderation. We are exploring the possibility of premium use for events in the future.