Best Period-Tracking Apps

Whether you call it Aunt Flo, The Red Tide, simply the Monthly Visit, a surprise period can be a real downer — not to mention tough on the laundry.

But the days of using pen and paper to keep track of menstrual cycles are past. Apps for period tracking have proliferated for both iPhone and Android. Some of these apps are simple calendars; others have space for tracking cervical mucus and body temperature to help women estimate when they are ovulating. Most apps will "learn" about the length of your cycle over time to best predict when your next period will occur.

Of the many highly rated period tracking apps available, our favorite isClue (free, iPhone,android)which bills itself as "confident, scientific — and not pink."