http://www.techradar.com/news/amazons-alexa-app-topped-apples-app-store-on-christmas >Image credit: Amazon Amazon's voice-controlled Echo devices were quite the popular gifts this Christmas, judging from the way the Alexa app shot up to the top of the list of the most popular free apps on the iOS App Store on Christmas Day. >It's slipped a bit since then, but only a bit. As of right now, it commands second place, sitting just behind YouTube.