Fertile window accuracy?

My fertile window according to this app, started yesterday the 12th... and I ovulate on Friday the 17th... my question is, how accurate has this app been for you ladies that are TTC? Have y’all ovulated on the same day the app says you will by taking an ovulation test? Or not? Also my CM today is kinda dry, also for the past 2 - 4 days I e barely had any EWCM, mostly water but not too watery. Idk what to think and it’s completely throwing me off and getting me upset and frustrated! I got AF on the 1st and ended on the 6th... AF is expected for Dec 1st. 🤞🏼🤞🏼 fingers crossed, that I conceive this month 🤞🏼🤞🏼 I’m 25, TTC #2, off of BC since Oct 4th, TTC for a month and a half.