https://arstechnica.com/gadgets/2017/08/cortana-and-alexa-are-coming-together-in-surprising-microsoftamazon-partnership/

By the end of the year, you'll be able to tell your Windows 10 PC "Hey Cortana, open Alexa" and talk to Amazon's personal assistant. Or if your Echo is in earshot, you'll be able to tell it "Alexa, open Cortana" to talk to Microsoft's assistant instead. Microsoft and Amazon are working together to ensure that their voice-driven digital assistants will be able to work together in a surprising collaboration.

Both companies have reach in areas the other does not; Microsoft says that there are some 145 million monthly active Cortana users on Windows 10 PCs, while Amazon has found success selling its Echo speakers into living rooms and bedrooms. With this partnership you'll be able to take advantage of Alexa's easy online shopping from your PC or Cortana's stronger calendar integration on your sofa.