[stephbu]

Pretty much every cellphone/app user dimension is available for a price on the open market. What you do think Facebook et.al, sells when an app user allows background tracking?

Is it unethical to study behavior of the populous? If anything bringing it into a clinical study probably brought more oversight in terms of ethical handling, and aggregation/anonymization of data than the source would provide.

[PragmaticPulp]

> What you do think Facebook sells

Facebook doesn't sell data. They place ads, but the data stays in-house.

[crtasm]

Facebook sells targeted advertising, they don't sell the underlying data AFAIK?

[stephbu]

Ads is just one of their businesses, consider FBLogin and 3rd party data-access e.g. full-name, date-of-birth, email address, friends, the list goes on...