Google has introduced a new feature to its Allo mobile messaging app that brings along the ability to create polls. The information was provided by the tweet from Amit Fulay, who is Head of Product (Allo and Duo) at Google.
— Amit Fulay (@amitfulay) April 3, 2017
Presently, you can only create polls for yes/no questions, meaning no custom answers at the moment. To use the feature, start with typing @yesno, followed by your question, and the poll will be created.