I have been using the app for two months - the second month I also purchased ovulation strips which helped verify my "window" as I wasn't quite sure if the app was tracking exactly right due to my periods being anywhere between 28-32 days (so there was wiggle room for accuracy). Anyhow, the app was great and really helped and just found out last night we are going to have a baby ☺️❤️ lots of love to all!