An assistance device for assisting with the use of a device for dispensing a liquid product in the form of drops having a tank including a connector for rigid connection to the dispensing device, an optical device arranged near a dispensing orifice, configured to provide information on the dispensing of a liquid drop by the dispensing device, a measuring device for measuring the inclination, configured to provide information on the inclination of the dispensing device connected to the assistance device, and a system for processing information on the dispensing of a drop and on the inclination of the dispensing device connected to the assistance device to provide information on the amount of liquid product dispensed. The invention also relates to a dispensing kit and a method for determining the amount of liquid product dispensed in the form of drops by a liquid-dispensing device, with the assistance device.