My Take
Kahoot is an easy to setup fun game for students. The games are fast paced and an element of drama is added by the background music. One of the best elements is that all students have the opportunity to respond to each question and you can download their responses in the form of an Excel spreadsheet. I really cannot think of a single criticism of the game. It work well, is fun and easy to use. They only suggestion I would make for the future is that they should consider plugging into the APIs of CMSs and gradebooks.
How I Use It
I have used Kahoot with my class to review before a test. The games are easy to setup and customize. You can select the time you want students to have to answer questions. You can also add images. Students can use their smart phones or computers to provide responses. The only challenge that I have run into is that students need to have a faster data connection. Some students how are using their personal data have run into problems trying to respond in time.