This is a tutorial for making a cheap eytracker with a webcam, Arduino and Matlab. Before running the matlab code connect Arduino to the computer and run the "Arduino_Matlab_serial.ino" file. This will allow you to make Arduino communicate with Matlab. Please follow the instructions in the Matlab code for tracking the eye movement. IMPORTANT NOTE: This is not a professional eyetracker, i just used it to monitor the position of the eye during an experiment. If you need to track a saccade, measure the number of fixations or a reaction time i suggest you to buy a professional eyetracker
The youtube tutorial can be found at this link
(Further info about Arduino Matlab communication without downloading any Matlab-Arduino toolbox can be found at this link https://www.youtube.com/watch?v=kr21ypVgb1M&t=13s)