Amazon’s Alexa virtual assistant is at the heart of its coolest recent product, the Echo home speaker. The virtual assistant is improving quickly to rival Siri and Cortana, with lots of useful integrations that let it control your lights, answer questions, order an Uber or adjust your house’s temperature. Amazon announced Alexa is coming to two new devices this week, the Amazon Tap and the Echo Dot. Both are interesting takes on the original Echo, designed to be used in slightly different environments.