Kahoot as an assessment tool

Kahoot could be a very useful tool to assess students in a fast and no-stressful way.
So, what is the problem? why don´t to use it?

Easy... there are not enought computers in the classrooms.
Solution: a TIC classroom with more computers or giving the permision to students of using their own devices at class. Second option seems to be costless and easy but... have we consider how well the wifi of our IES are working? Could the wifi of our high school support that?

Teachers can improve many things but there are "things" out of our hands...

Here an example I had use to assess some students at the 2nd ESO:

Reacciones químicas en la naturaleza