Brake mode is available for ACE and ICON2 lights via the See.Sense smartphone app on iOS andAndroid. When brake mode is turned on, the light will only react to braking. This is because we felt that if the light is reacting to light, movement and braking, it would be too much and also collectively drain the battery faster. Please note that the feature is not currently available for the original ICON.
The light will turn partially on solid mode when it senses medium/heavy braking. When you finished decelerating, and increase speed again, the light will begin to flash normally again. The reason it only reacts to medium/heavy braking is that if the limits were much smaller, then the light can react to much smaller changes in speed that do not call for it. i.e. slowing down when you being to climb a hill or any other natural decelerations.
There is a video below demonstrating what brake mode looks like: