Thanks for including the mirror, OP.

Companies that obtain mobile phone location data generally do it in two different ways. The first is through software development kits (SDKs) embedded in ordinary smartphone apps, like games or weather forecasters. These SDKs continuously gather a user’s granular location, transfer that to the data broker, and then sell that data onward or repackage it and sell access to government agencies.

The second is through real-time bidding (RTB). When an advert is about to be served to a mobile phone user, there is a near instantaneous, and invisible, bidding process in which different companies vie to have their advert placed in front of certain demographics. A side-effect is that this demographic data, including mobile phones’ location, can be harvested by surveillance firms. Sometimes spy companies buy ad tech companies out right to insert themselves into this data supply chain. We previously found at least thousands of apps were hijacked to provide location data in this way.

I really despise these practices. I don't know how people can build these tools with a clear conscience.