We mostly watch news and sports in my house. So unfortunately, live TV. Occasionally we watch other things. I mute the commercials and browse my phone when they’re on.
But I would love a TV that is smart enough to auto hide & mute every kind of ad. Even little logos on the athletes’ uniforms. Hide the ads on the pitcher’s mound. Hide the billboards and signs in the stadium. Show some cool little generic animation, music video, or slide show during commercial breaks. Hide the damned popup window ads and scrolling ads that some channels do. Remove product placements from movies and shows. Basically make all ads completely vanish.
It’s not a device that Sagan goes into much detail about, aside from it being a new and less-than-reliable technology in the early parts of the story. I always imagined it as a laptop-sized, wireless fax machine using cellular networks to share data. Characters mostly use paper documents throughout the book, and while there are some sci-fi technologies like holographic displays that advance throughout the story, Sagan never describes anything like portable computers or smartphones. Even the internet(or its closest approximation) never goes beyond a rudimentary data-sharing network for astronomers, never open to the public.
A quick google search tells me EFax would probably work over that network, sending documents from a desktop straight to someone’s Portable Telefax like an email, so you’re not far off.