Monitoring and controlling fermentation activity is crucial in order to achieve desired results that are as close as possible to the standard recipe. Temperature Monitoring is the normal and most practical method used by brewers.
Plaato Airlock estimates fermentation using "BPM" - bubbles per minute [0-800] which is the count of the bubbles (Co2) produced from the fermentation activity in your fermenter. The %ABV is estimated based on this, your Original, Specific and/or Final Gravity.
Your Plaato Airlock will also monitor the temperature throughout the fermentation process and display temperature on your monitor screen.