• Graphical biorhythm chart based on your time of birth
• Estimate your physical, emotional, and mental fitness for any day in the future
• Calculate your anticipated most critical days within the next three months
• Highlight your estimated overall positive or negative phases
• Manage a list of your friends` birthdays and calculate their biorhythms, too

What are Biorhythms? According to the biorhythm theory (invented around 1900 by the psychologist Swoboda and the physician Fliess), a person`s physical, emotional, and mental fitness undergoes determined oscillations between negative and positive phases. The ups and downs can by calculated based on the person`s date and time of birth. According to the theory, a biorythm curve crossing the border from positive to negative (or vice versa) indicates a critical day. If two or all three curves cross the zero line on the same day, this indicates a very critical day. If all three curves are high up, or low down, an overall good, respectively bad, phase is assumed. Some people include their biorhythm in their time management, for example to plan important dates or phone calls.