Alexagate prevents your Echo from hearing you. Clap three times, or tap the Alexagate three times, and it toggles off so that you can talk to your Echo like normal. Claps three times again, and you’re once more assured of privacy.
Alexagate uses pulsed ultrasound to jam the Echo’s microphone. What’s even better: Ultrasound is beyond the range of adult human hearing, so you won’t even be able to tell it’s happening!