The holiday shopping season has been good to Amazon, and particularly Echo.

Now that Christmas 2016 has passed, Amazon has some insightful metrics on its sales from the bulk of the holiday season. Predictably, Amazon Echo sales were dramatically higher than last year: nine times higher than the same period last year, in fact. That is of course fueled by the massive increase in popularity and injection of Echo into popular culture, but also by the launch of the Echo Dot and Echo Tap to diversify the lineup.

Amazon Echo Dot

Keeping up another tradition, Amazon isn't releasing any sort of real sales numbers. Other than saying there have been "millions" of Echo devices sold in all of 2016, we don't know just how popular these connected speakers are. Continuing the trend, Amazon says that its Fire TV Stick and Fire tablet topped its best-sellers list, but of course without the context of what other devices are included in the list and how many were sold.

The Echo is amazingly popular — we just don't know exactly how many are sold.

No matter exactly how many are out there, we know a ton of Echo devices are in use. Amazon says some of the most popular requests of the Echo this season were for cocktail recipes, chocolate chip cookie recipes, holiday movies like Home Alone and Elf, and millions of holiday songs with Frank Sinatra's Jingle Bells and Mariah Carey's All I Want for Christmas Is You topping that list.

Speaking to the holiday shopping season more broadly, Amazon says that it shipped over one billion Prime and self-fulfilled items this holiday season. December 23 was the biggest day ever for same-day Prime Now deliveries, with three times more deliveries than last year. Not surprisingly, 72% of Amazon customers around the world shopped using a mobile device for the holidays.