You're assuming it's developed in the west. They could've just outsourced that work, too. Here in India, I don't see too many developers who give a damn about user privacy. From privacy international's report on menstruation apps stealing data [1], two of the worst offenders (Maya and My Period Tracker) were from Indian companies.

1: https://privacyinternational.org/long-read/3196/no-bodys-bus...