"Transparency merely describes what the system is," he said. "If the system is unfair, a description of an unfair system is relatively valueless."

Other participants disagreed, saying a transparency standard would have value on its own. "Transparency alone has significant, inherent value," said Steve DelBianco, executive director of NetChoice, an e-commerce trade group. "Transparency about the status quo ... enables consumers to be informed, make choices about the services they use, or to change the settings in the services they use."

Transparency practices have "tremendous" benefits, added Jon Potter president of the Application Developers Alliance.

App developers are interested in transparency and mobile privacy, he said. App developers want to see a single, uniform best practice for mobile privacy, he said.

"They don't like to be sued," he said. "They don't like getting letters from Congress. They don't like bad press. More importantly, they want consumers to trust their app."