AsthmaDiary is a mobile app and web service for monitoring asthma symptoms. It offers a quick and easy way to collect rich and timely information on asthma symptoms, triggers and medication used as well as daily peak flow values. Based on geographic location, the information can also be enriched with environmental information on air quality and weather and their possible impact on asthma. The history of a user’s asthma symptoms during a day, week or month is represented in statistics and visualizations. With the help of these, the disease can better be managed and the trends in asthma symptoms easier identified.