How does OvaGraph display the ovulation date and cover line?

OvaGraph interprets your BBT readings using a combination of algorithms in addition to the cervical mucus/fluid and vaginal sensations that you’ve charted. Generally speaking, once an appropriate temperature rise is detected near cycle days that you see fertile quality cervical mucus/fluid and/or experience fertile vaginal sensation, followed by temperatures that remain elevated for a minimum of 3 out of 4 consecutive readings, OvaGraph will display the likely ovulation day with a purple vertical line and a coverline with a purple horizontal line.

If your Chart Settings is set to BBT Mode:

OvaGraph automatically interprets your BBT data and will display the ovulation date with a purple vertical line and the cover line with a purple horizontal line. The green shading on the graph indicates when you were most fertile in the cycle, based on the calculated ovulation date, with light green indicating "high fertility" and dark green indicating "peak fertility".