This program is the server side to the Learning Tracker app. It is designed to enable teachers to send questions to students and receive their answers in real time. It doesn't require an internet connection but all the devices (students' smartphones and teacher's computer) must be connected to the same Local Area Network (LAN).
If you want to test it for yourself, you can download the "LearningTrackerForTeachers" folder which contains the jar file, a folder with questions to import and the folder with the corresponding pictures.