US Federal authorities have begun an investigation into how smartphone applications use personal data, according to US reports.
Mobile music streaming app maker Pandora Media has received a subpoena in connection with the probe, according to the San Francisco Chronicle.
The proceedings of grand juries are normally kept secret, but Pandora disclosed the investigation in a regulatory filing in connection with a planned initial public offering, according to the Financial Times.
The company says it believes the investigation, which has not been confirmed by US authorities, is industry-wide and covers the information sharing processes of several popular applications that run on Apple and Android mobile operating systems.
The apparent investigation comes amid increasing concern over personal data sharing after the Wall Street Journal reported in December that apps that rely on advertising as their source of revenue routinely collect and distribute data about users.
The paper's investigation found that Pandora's iPhone app sent location and demographic data about its users to eight trackers, mostly for advertising purposes.
Privacy groups have welcomed the idea of an investigation. They say a lack of information and rules about how apps share information put users at risk.
In turn, app makers such as Pandora have warned that new regulations will have a negative impact on services and their ability to earn revenue from advertisers.
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