Alexa, Amazon’s virtual assistant, is in more than 3m US homes via the Echo speaker. Now it’s available in Britain – but what’s the attraction?The very first thing you’ll want to do with your new Amazon Echo is learn a few basic voice commands. Saying “Alexa: stop!” will immediately cancel whatever activity is going on; to make music louder or quieter, say “Alexa: volume up” or “Alexa: volume down”. You can jump to a specific volume level by saying a number from one to 10: “Alexa: volume one” will turn the audio down to a whisper, while “Alexa: mute” will silence the Echo altogether