Echo devices are designed to detect only your chosen wake word (Amazon, Alexa, Computer, or Echo). The device detects wake word by identifying acoustic patterns that match the wake word. Once the word is detected, audio begins streaming to the cloud, including a fraction of a second of audio before the wake word. No audio is stored or sent to the cloud unless the device detects the wake word (or Alexa is activated by pressing a button).
Alexa app has awesome features and skills for you. You can easily make calls or messaging with Alexa. But Alexa calling doesn't support calls of the numbers - emergency service numbers, premium rate numbers, etc.
Also, Know all about Alexa setup, echo dot setup, echo app, alexa.amazon app, download Alexa app, Alexa app, Alexa login, Alexa echo app, echo dot app, Alexa dot app, Alexa app, Alexa app for Android, Amazon Alexa dot, Alexa app windows, Alexa app for Mac, Alexa setup, Alexa app for Windows 10, etc.