Menti: You can create mini quizzes, likert scales, open ended response questions, word cloud responses, multiple choice questions - take your pick! Students respond and you collect data.
Trello: This webiste lends itself to list-making and organization. Teachers could create exit tickets this way and have students respond with emojis, words, or card colors (green, yellow, red). Then you can filter the results to look for areas in need of support.
Padlet: Similar to Trello (but no longer free), Padlet allows students to respond to a "sticky-note" form through video response, pictures, or text.
Answer Garden: Ask your students a question and then allow them to respond in 140 characters or less. The result? A word cloud displaying student understanding.