In an interview with The Verge, Amazon's SVP of devices and services, David Limp, has revealed how many devices have been sold that have Alexa built into them. Apparently, over 100 million speakers, smartphones, gadgets and other pieces of hardware have been sold around the world featuring Amazon's virtual assistant.
https://www.notebookcheck.net/Amazon-executive-reveals-sales-of-over-100-million-Alexa-enabled-devices.391541.0.html