BBC: How period trackers share your private details

“This may or may not bother you. But simply revealing the fact that you use a reproductive health app can have consequences, says Sara Geoghegan, director of the Consumer Privacy Program at the Electronic Privacy Information Center, an advocacy group.”

“Among other things, it could let law enforcement know there’s a trove of health data to get their hands on.”

“‘Data collected from a period tracking app can be part of a whole tapestry woven from many different threads of surveillance,’ says Geoghegan. ‘That can be very revealing.'”

Read more here.