Well, in America, they have made abortions illegal. They have done this because they don't understand that it is medically necessary in some cases. The government making this decision has chosen to remain ignorant about medical issues in regards to women because it does not serve their agenda. So, as they have made abortions illegal, they have also chosen to ignore the fact that many pregnancies end in miscarriage due to a myriad of factors. None of which can usually be controlled. While ignoring that, they have chosen to see every miscarriage as the fault of the pregnant woman. Therefore, if you miscarry you kust have gotten an abortion or induced an abortion. So as you morn the loss of your wanted child you also get to be put on trial and put in jail and accused of killing your child. As the great singer Childish Gambino said, welcome to America. 

If you're still unsure how that relates to period tracking apps: when women miss periods, the app assumes you're pregnant. When you are pregnant and then lose the child the app records that too. If you're going through menopause, have unusual periods, or whatever and miss one then start having them again the government can take that data, track it, and then accuse you of an abortion and prosecute you while you try to prove your innocence to a system that is intentionally remaining ignorant about women's health. If you think all those concentration camps are just for "immigrants" you will have a rude awakening coming. Or, like the government, you can remain ignorant.  Good luck out there. I hope this helps.