You can already start calls to Alexa devices from Amazon's tablets, but it's now possible to receive those calls, too. As of December 5th, people with recent Fire HD 8 (2017 and 2018) and Fire HD 10 models can take Drop-In calls and intercom-style Announcements when they're in Show Mode. This will mainly be useful if you have a Show Mode charging dock, which invokes the mode automatically. If you're in that position, though, it could be very helpful -- you could tell your kids it's time for dinner without buying another Echo or (gasp) walking across the house.