A Philadelphia-born brother and sister are making profitable music, selling an active singing-therapy system to senior centers and retirement homes across the country. Fittingly, it's called SingFit.

The first product from SingFit, a Silicon Valley-style tech start-up based in Los Angeles, is specifically marketed to those 55 and older to improve memory, boost mood, and fight dementia.

Co-founder siblings Rachel Francine and Andrew Tubman grew up in Germantown — she graduated from Philadelphia High School for the Creative and Performing Arts in 1987; he graduated Chestnut Hill Academy high school in 1986. Both attended Germantown Friends for elementary school.

"We digitized a music and speech-therapy technique called lyric prompting or coaching," said SingFit CEO Francine, who started the company in 2011 with Tubman, a music therapist with a degree from Temple University.

The siblings raised seed money to create the mobile apps at the heart of the program. Among those who invested their personal money is Mike Fowler, president of Affordable Housing Partners Inc., a Berkshire Hathaway Inc. subsidiary. SingFit also has a direct-to-consumer app in the iTunes store.

How did they get the idea? "Our dad, Louis Tubman, was an opera student and singer," Andrew Tubman explained. "He got kicked out of Curtis, and he's quite proud of that!

"There's a technique called lyric prompting in opera, so when a lead singer goes into rehearsals of an opera, there's someone in the wings feeding the words of the song to those who are weak in their memorization."

Tubman and Francine saw an opportunity in using lyric prompting in singing technology for seniors.

"Dad always used to say, `Why can't I have the opera prompter in the car with me?' And while Andy and I started our own careers, we had this idea implanted in our heads," Francine said.

The road to SingFit — previously known as Musical Health Technologies — was a winding one. In his studies, Tubman discovered that the prompting technique was actually standard in music and speech treatment for such conditions as dementia, autism and spectrum disorders.

Over the years, he said, "we played with the idea of how to use prompting technology and scale it up using music as medicine."

After college and a few years working at Philly's beloved TLA Video, Francine pursued a graduate degree and took jobs in California with CitySearch and Al Gore's Current network. Tubman finished his music-therapy degree and traveled to Los Angeles to visit his sister.

"I realized, 'Whoa, I never got the memo about how nice it is out here,'" he recalled. Tubman set up a private music-therapy practice in Los Angeles, and soon their father moved out to California, as well.

To be clear, "SingFit isn't karaoke," Francine said. "That isn't designed for therapeutic outcomes. This isn't just grandma humming along to music."

What's the difference? "When listening to audio or hearing someone sing, you light up a small part of the brain. But once you yourself actively make music, you activate the whole brain. Then it's exercise, similar to yoga; you engage respiration, emotional centers, release oxytocin, seratonin, dopamine, melatonin, cortisol — all are regulated through singing."

SingFit Prime is a product that allows an activities assistant or coordinator at a senior home to do a therapeutic music program.

"Different caregivers can be trained on it and use it, and there's a thematic playlist that incorporates movement and four levels of trivia for cognitive stimulation," Tubman said. Considered a brain exercise, "if you do it two to five times a week, it's really a neurological gym," Francine said.

Indeed, SingFit's website has videos showing Tubman singing and dancing with seniors using the proprietary "prompting" technology, which calls out the lines right before they are to be sung.

In 2013, SingFit signed its first customer: Aegis Living, based in Washington state, which has 30 retirement communities. The company just renewed for a fourth year.

"That was really an `Aha!' moment for us. We trained three different people to work with 70 seniors, and from that point on, thousands of older people were singing three to four times a week. We took music therapy and scaled it up. That's amazing," Francine said.

Thus far, their company has no East Coast clients. But SingFit is in talks to sign up with a national retirement and long-term-care community, which they can't yet disclose. The cost for a yearly subscription is $2,400 for senior-living communities and slightly less for adult day programs.

SingFit's retention rate is about 93 percent once a facility signs up.

"As we're growing, we're still delivering a product people appreciate," Francine said. Better yet, she added, they built a company together, and "it's a miracle we haven't killed each other yet!"