The Towers family bought Alexa, Amazon Echo's intelligent personal assistant, just before the Rev. Dr. Martin Luther King Jr.'s birthday. So their first request of her was to hear the civil rights leader's most famous speech.

"There was Martin Luther King's 'I Have a Dream' speech, in his voice, blasting through my kitchen," Cindy Towers, 53, said.

Beyond history lessons, the family asks Alexa to play music, report the weather, provide store hours, and set their daily alarm clock through Echo Dot, a streaming audio player that becomes an off-site hub by her bed in her Society Hill home.

"She's the best assistant you could ever ask for," said Towers. "She's in the top five of conveniences that have made my life easier. In my world, speed and seconds matter. You don't have to do anything - you just talk to her."

Towers' children, Alex, 14, and Jack and Mackenzie, both 12, use it too, often to hear sports scores. They'll occasionally ask a homework-related question, but when working on their laptops, the computer's web browser is easier to use.

Since Siri was introduced in 2011 as part of the iPhone 4S, other companies have followed to offer customers voice-activated personal assistants, most notably Microsoft's Cortana, Google's Google Assistant (now part of Alphabet), and the newest entry, Facebook M.

Launched in November 2014, Alexa, around $180; its smaller version, the Echo Dot, $50, released in 2016; and Google Home at $129, released in November, are currently the only stand-alones - not part of a smartphone, computer, or other device. Cortana's stand-alone unit is scheduled to debut in February.

Polling a panel of online consumers in May, "38 percent said they used a digital assistant," said Ben Arnold, industry analyst with the NPD Group, a market research company in Port Washington, N.Y. "That number's gone up fairly significantly, probably close to 50 percent with Amazon and Google's stand-alone units. A lot of people have tried Siri on their phones, but it's probably trending toward more of these tabletop speaker devices as that market expands."

What's made the assistants - which are able to hear and respond after deciding on the best answer - so prevalent is the fact that the accuracy has gotten more sophisticated, said Drew Morrisroe, CEO of CTN Solutions in Blue Bell, which provides IT support and network services. "They can be right most of the time."

And "most of the time" can be very helpful when all you're asking of it are menial tasks - turning off the lights, looking up a recipe, having emails or books read aloud - and especially gratifying for more dramatic interventions. Some local hospitals use it to improve patient behaviors to speed healing. In June, after an Australian woman saw her year-old daughter turn blue on a baby monitor, she rushed to perform CPR while shouting to Siri to call an ambulance. The ambulance arrived and the child made a full recovery.

"We're used to thinking of technology as hardware, but assistants innovate on the software side - speech recognition combined with [artificial intelligence] to help us get what we need," said Jonah Berger, Wharton professor and best-selling author of Contagious: Why Things Catch On. "Now we are tethered to our devices, but in the future, we will be able to get information by voice."

Some people need convincing: When Alison Goldberg's husband bought an Amazon Echo as a joint Mother's Day/Father's Day gift last year, she wasn't impressed.

"I initially thought, 'Why do I need this?' " said Goldberg, 45, of Voorhees. "I felt really awkward talking to it - the fact that you had to say things in such a deliberate way."

But over time, she's come to appreciate the convenience it offers - being able to build a grocery list the moment something runs out, getting recipe conversions with batter-laden hands, answering Jeopardy! questions with her kids. "It was a matter of learning the right phrase - 'Alexa, please ask 'Our Groceries' to add apples to BJ's," she said, demonstrating that Our Groceries was the prompt to get to the appropriate app.

Alexis Garvin got her Echo for Christmukkah and, so far, uses it mostly to listen to music and get daily news, weather, and traffic. She expects it to become more impactful over time. As for her privacy - everything recorded by Alexa lives in the cloud - she's come to accept she might lose some.

"Five years ago, you would have never said that you'd be driving in other people's cars with Uber or you'd be sleeping in other people's houses with Airbnb," she reasoned. "I've chosen to embrace it."

Morrisroe of CTN Solutions is less convinced. "I get wary around the privacy because when you interface with Alexa, it records all of things you said to it and all of the questions you asked it," he said. "All that data is going up into the world somewhere."

(Concerned users can mute the microphone or delete conversations after they are recorded.)

Since getting his Echo in December, James Macfawn hopes to reduce the repetitive, mundane tasks that consume his time: turning on and off lights, arming the alarm, locking the door.

He places the main unit on one floor with Dots on each of the other three floors in his Bella Vista home. Using location-based services, the device turns on his lights when he is two or three blocks from home. He's also tried to use it to order products online, but so far, "it isn't completing my requirements," Macfawn, 51, said. "It comes up with one solution, and I can do that faster on a computer. Maybe that's my ignorance at this stage, but my goal is to give it a set of tasks to manage my household."

Patients at Thomas Jefferson University Hospital will soon have access to bedside virtual assistants, which, among other things, will be able to remind them to walk at periodic intervals to speed their recovery, dim the lights, list visiting hours, play music, and narrate bios of their medical staff. In conjunction with IBM Watson Cognitive IoT and Harman International, Jefferson, which is calling its assistant a "cognitive concierge," will be phased into hospital rooms, in their clock radios, beginning in mid-March.

"This groundbreaking innovation," said Neil Gomes, Jefferson's chief digital officer, "helps build a relationship with the patient, speeds up response time, and allows the physicians and nurses to focus their time on clinical efforts."