As many as 50 million people now have a record of their menstrual cycle on their personal devices. But how much should they rely on their period tracker for reliable and accurate information about menstruation and fertility? Some apps are free, and some make you pay. All are part of a booming industry known as “femtech”.
But evidence about the apps’ accuracy and quality suggest they don’t always help users gain a better understanding of their bodies. Here’s what period-tracking apps can – and can’t – tell you about a woman’s cycle. How do period trackers work?.
