[detaro]

Phones are not disguising as a device that doesn't capture sound, people are considered aware that phones can communicate. A phone with a special "spy mode" in which it looks like it is turned off but actually is working like one of these watches might trigger the law, since a person seeing it turned off could have a reasonable expectation of not being captured.

You hiding a phone isn't the fault of the product type, and thus only your actions might be illegal, not phones themselves.

[jon_richards]

Most phones do have a "spy mode", it's just activated by the NSA.

http://money.cnn.com/2014/06/06/technology/security/nsa-turn...

[thaumasiotes]

> A phone with a special "spy mode" in which it looks like it is turned off but actually is working like one of these watches might trigger the law

All phones have this mode; it's a feature to consume less battery by shutting off the display when you're not using it.