NearPod for Class/Workshop Polling – ProfHacker - Blogs - The Chronicle of Higher Education
Mentimeter - Turn opinions into tangible data, in real-time
Mentimeter: Polling service (audience response system) with value-packed free option, recommended by @wstagnaro
10 Useful Web Tools for Creating Online Quizzes and Polls ~ Educational Technology and Mobile Learning
Free resource of educational web tools, 21st century skills, tips and tutorials on how teachers and students integrate technology into education