Cm doesn’t mean ovulation. Ewcm mean sperm can swim in it and the app doesn’t know your body. If you want accuracy you need to actually track with opks to let you know when your about to ovulate and BBT to confirm ovulation and you will know when you ovulated, dpo, luteal phase length (is from the day after ovulation to period which stays the same each cycle give or take 1-2 days. Average length is 12-14 days give or take 1-2 days.) when period is coming by temp drop or if you miss your period and your temp stays up then there is a chance for pregnancy