It's like a glimpse into the future. The latest viral sensation, FaceApp, uses artificial intelligence to "age" the face on peoples' phones by decades, giving them a look at their older selves.

The results -- if the millions of Facebook and Instagram posters can be taken at their word -- are pretty amusing. Everyone can share a laugh at the expense of their wrinkled, balding future avatars.

Of course, the Russian-made app itself is collecting user data on an unprecedented scale, and sharing it with lord knows who. It's a privacy nightmare. But it hasn't stopped folks from trying to reach out to their senior selves.

If only the app went more than skin deep, and offered a look at the world users will be living in when they actually reach old age.

For one, it will be grayer. In a little more than 15 years, older adults will outnumber kids for the first time in American history, the U.S. Census Bureau reports. By 2035, the bureau said, people age 65 and over are expected to number 78 million, while there will be 76.7 million children under the age of 18.

"By 2060, nearly one in four Americans will be 65 years and older, the number of 85-plus will triple, and the country will add a half million centenarians," the bureau wrote in a report released last year.

The demographic shift brings with it a raft of challenges ranging from housing to retirement savings to dealing with the medical issues that arise in our later years.

Take, for example, the emerging crisis in elderly housing. About 25 million Americans "aging in place" in their own homes already need help with daily activities ranging from bathing to cooking and running errands. Already, many are not getting the help they need from overwhelmed relatives or a cash-strapped senior service system. A recent Johns Hopkins study noted that 60 percent of seniors with "compromised mobility" stay inside their homes rather than leave the house; 25 percent said they often remained in bed.

There are solutions such as changing rules that keep Medicare from paying for non-medical devices like raised toilet seats and shower grab bars, and building more affordable supporting or assisted housing.

While we're on the topic of entitlements, 2020 will be the first year in almost four decades that Social Security will pay out more in benefits than it takes in, forcing administrators to pull money from its rainy day fund. That means that, unless Congress addresses the issue, today's FaceApp users can expect their Social Security payouts to be lower than those of their parents and grandparents. And this from a generation that for a variety of reasons has had difficulty saving for retirement.

"If you look around the see how much middle-class people approaching retirement have in their 401(k)s, they don't have enough," Alicia Munnell, director of Boston College's Center for Retirement Research, told the Boston Globe. "And most lower-income people don't have 401(k)s. So Social Security is going to become more important to most people."

Yet the system's slide to insolvency means future retirees could see benefit cuts of as much as 20 percent.

And when today's 30-somethings age into seniors, they will be the beneficiaries of better health care. The federal government, for example, has set a 2025 deadline for next-step solutions to Alzheimer's disease through the National Alzheimer's Project Act. But even if the deadline is met, the population shift threatens to swamp any modest progress made.

Today, 5.7 million Americans live with Alzheimer’s, with the long-term cost of the disease nearing $290 billion. In 30 years, an estimated 14 million Americans will have the disease and the cost will exceed $1 trillion.

“The disease trajectory of Alzheimer’s is forcing our hand,” George Vradenburg, the co-founder and chairman of the UsAgainstAlzheimer’s advocacy group, told Forbes magazine. “The health care system needs to start preparing now to more effectively detect, diagnose, address and support Alzheimer’s patients and families today and over the next few decades.”

The challenges are sobering, but they must be met if there's any hope those FaceApp oldies are really smiling by the time we age into their wrinkles.