If I wanted to keep track then I definitely would need a calendar. My period is all over the place. Sometimes is 4 or 5 weeks in between instead of the usual 29 ish days, and sometimes I get two a month. There’s no set schedule for me unfortunately, and it’s more erratic as I get older. On the plus side I’ve never had cramps or the other usual symptoms, just had to make sure I have a tampon or pad with me at all times. So yay I guess.

It’s absolutely a way to collect that data and prosecute women. Look at the permissions of any app before you download it!!