IBM (IBM) CEO Ginni Rometty and Apple (AAPL) CEO Tim Cook stood on stage together this morning at IBM’s Watson headquarters in New York City to announce a new partnership with Japan Post Group that aims to, ultimately, address the enormous accessibility challenges facing the world’s growing population over age 65.

Rometty and Cook silently flanked Japan Post Group president and CEO Taizo Nishimuro, himself nearly 80 years old, as he spoke for more than 20 uninterrupted minutes about Japan’s rapidly aging population and how IBM’s apps and services, and Apple’s iPads and iPhones, would help better connect the country’s senior citizens to society.

“Japan is home to the fastest-aging society in the world,” Nishimuro said, gingerly and in halting English. Thirty-three million people—about 25% of Japan’s total population—are age 65 or older, he said. That’s going to increase to 40% in coming years.

Meanwhile, Japan Post Group—a postal service, a bank, a life-insurance provider—is moving toward what some believe will be the world’s largest IPO, larger than Chinese e-commerce darling Alibaba (BABA). It’s all a part of prime minister Shinzō Abe’s economic plan, known as Abenomics, Nishimuro said.

“I gave myself a mission,” he said. “Transform Japan Post Group into an integrated lifestyle support company.”

As Nishimuro spoke, Cook, to his right, looked on with a twinkle in his eye and an admiring smile that blossomed into a full grin when Nishimuro mentioned the words “iPhone” and “iPad.” Rometty, to his left, nodded and smiled every few lines.

The initiative breaks down into several parts. Apple will supply its iPad, whose operating system, iOS, already has a wealth of built-in accessibility features including settings for people with impaired vision or hearing, such as large type or dictation. IBM will custom-build applications through its Global Business Services group—its leader, Bridget van Kralingen, introduced the trio—that will include reminders or alerts about medications, exercise, and diet; as well as services for grocery shopping and job matching. All of them will run on IBM’s MobileFirst for iOS cloud computing service, and Big Blue will layer in its own analytics, accessibility, and natural language technologies. Finally, IBM will train Japan Post employees to help them help the elderly.

The executives spoke a great deal about helping Japan Post cover “the last mile” to reach the 115 million adult citizens in Japan—it has 24,000 post offices and 400,000 employees—and taking eventual success to the rest of the nations of the world, which aren’t far behind. (In the U.S. alone, 10,000 people turn 65 every day.)

“Today is about reimaginging life for what is the largest generation in human history—seniors,” Rometty, 57, said.

It’s a big push for Apple and IBM. Their first partnership, announced almost eight months ago and aimed at “reimagining work in the enterprise,” now spans 11 industries and 22 apps. “At our heart we’re a solutions company that’s underpinned by these new technologies,” Rometty said.

Cook, 54, took great pains to underscore how the partnership would improve people’s quality of life. “For someone that has been a long-time studier and admirer of the Japanese culture, there is no surprise that, in a culture that respects the elderly and the wisdom of the elderly, this will start in Japan,” he said.

Cook mentioned Apple’s HealthKit and ResearchKit efforts as well as the health and fitness services available on the company’s new Watch. He also recalled what made the iPad such an initial success: its simple, intuitive interface. “For children, an iPad is often their very first device,” Cook said. Add assistive features to the mix and you can “help people who are marginalized in some way and empower them,” he added. “We think this kind of independence is key.”

“This isn’t about getting excited about improving the cost curve,” Cook said, raising his voice. “It’s about improving quality of life.”