California is poised to enact a consumer-friendly law requiring smartphone manufacturers to install "kill switches" -- that is, antitheft technology that would be activated by the carrier when a consumer alerts it that a device has been stolen or lost. The technology not only wipes the device of personal data but also renders it inoperable. There are some legitimate security concerns over the kill switch mandate. Though security experts tend to support the bill in theory, they fear the devil could show up in the details.