Amazon Echo's 5 best new features

Almost every Friday — and sometimes more frequently — I get an email from Amazon, with a subject line like, "New features have been recently added to Amazon Echo,"  the company's $180 smart-home virtual assistant and wireless speaker.
I don't know of any other piece of tech hardware that receives so many new features so often. Seriously. Since Jan. 1, Amazon added at least 10 new features, or feature upgrades, to Echo at the rate of about one per week. (A full list of Amazon's&