This article explains how to use the Amazon Alexa voice assistant app on your Android device via the Amazon Alexa app for Android. Instructions apply to all Android mobile devices, regardless of manufacturer.
How to Use Alexa on an Android Phone (How to Install Amazon Alexa on ANY Android Phone)
To use Alexa on Android, first download and install the app:
Download the Amazon Alexa app from the Play Store.
Open the Amazon Alexa app and log in with your Amazon account details (or create a new account if you don't have one yet).