When do you actually start ovulating?

Ok so we are ttc and gave been for awhile and were told to increase our chances of a girl (we have boys already) to have sex like every day after period until a day or 2 before ovulation. Ok so question is according to this app, would we stop before it turns green? Or keep doing it until "peak day" is peak day actual ovulation or is when the bubbles in this app start turning green actual ovulation?