A report released Tuesday by the Norwegian Consumer Council, a government-funded nonprofit organization in Oslo, describes how apps on our phones systematically violate users’ privacy collecting and sharing information with third-party advertisers without users’ knowledge or consent. The report "demonstrate[s] how every time we use our phones, a large number of shadowy entities that are virtually unknown to consumers are receiving personal data about our interests, habits, and behaviour." For example, some apps share users' dating choices, location, and/or ethnicity. One app shared information with more than 300 advertisers or other companies.
The report is here. A New York Times article on the report is here.
Although the article points out that the sharing practices may violate data privacy laws, such as laws in the EU and California, the U.S. has no nationwide data privacy law.