My Take
Overall I am a big fan of Kahoot. It is easy to set up, and use in the classroom. It engages students and is a fantastic way to help students actively participate in a class. It is a student favorite and as a teacher it is a favorite of mine as well! My only way that it ca be improved is to increase the types of questions that are possible to use. Right now only multiple choice is supported and students could benefit from short answer, matching, etc.
How I Use It
I use Kahoot in my classroom for reviews before exams as well as for study sesssions to gage the current understanding of my students. Typically I will arrange students into teams and have each team compete against each other for a small prize like extra credit. This always engages students and is a great way to review and gage understanding.