Abstract
We have developed and released a web-based clicker system named "bgClicker" that can push the students’ feedback to teachers in real-time during the lectures. Students use their own smartphone/tablet devices in order not only to respond to teachers’ questionnaire but also to push their feedback such as opinions，questions and requests to the teachers’ receiving device. The teacher will set threshold values beforehand，so that he/she will be notified (by an alarm) when the particular number of students push the particular feedback button. "bgClicker" is relevant to improve students’ appropriate comprehension in large classes and is available for free in non-commercial use.
