This can also be a problem in my opinion. Imagine you are only able to enter "confused". Then as soon you are using this app in a class room everyone who sees that you are using the app knows that you will enter "confused". This is a problem for many people I guess. You don't wanna lose your face sometimes. Hm - one solution to this could be to make the UI of the app absolutely generic or exchangeable. I would also build in a random delay between the "tap" on the button and the actual transmission of the data to the "lecturer". The delay can be minimal but this makes it hard to track it back to the source.