Whatever happened to latchkey kids? That group of kids that for short bursts looked out for themselves until parents finished work? Oh, they're around. But now they're called free-range kids and that sometimes leads to police investigating a case of neglect.

But letting your child ride unaccompanied in a car with a stranger has become a somewhat acceptable, growing form of outsourced parenting. In Phoenix, two national ride-hailing services HopSkipDrive and Zum began operating within a month of each other this summer, joining VANGo, which started in the spring.

"We are seeing tremendous growth in our existing market as well as massive demand to launch new markets," said Joanna McFarland, CEO of HopSkipDrive, which launched in Phoenix in July.

After Phoenix, HopSkipDrive expanded into Houston to became its 10th market. The service now operates in six states. One of its competitors, Zum, which serves parents and schools in transporting children in the San Francisco area and Los Angeles expanded into Phoenix, Miami, Dallas, Chicago and San Diego this summer.

The ride-hailing services promises a safe ride for kids to and from school, to soccer practice, dentist appointments or anywhere else time-crunched parents need.

While one parent said using the service was better than leaving her child home alone, another isn't so sure the background checks are enough to prevent crimes. The companies assure parents their services are safe.

How 'Uber for kids' services work

The services are often referred to as "Uber for kids." And although parents, and teens themselves, use Uber and Lyft, the companies have polices instructing drivers not to pick up passengers under 18.

More:Parents, would you let your kid ride an Uber or Lyft by themselves?

Like adult ride-sharing, HopSkipDrive and other kid-transport services like Zum, VANGo, Kango and Bubbl, use apps.

These are the offerings among the various apps:

Unaccompanied transportation for children 3 to teens

Car and booster seats supplied

Price-lowering for car pools

A fare estimator

Newer, clean cars

Ability to track children on their journey

Escort door-to-door service

Notice of a child's safe arrival

Advance booking or for one service

Same-day booking for last-minute trips

McFarland said 90% of parents use the service to get their children, the dominant age being 11 and 12, to or from school and after-school activities.

"With more parents working and bell times being right when parents need to be at work, especially at 3 o' clock when school ends, it doesn't mean mom and dad are out of work," McFarland said. "It can be a huge challenge to manage all that."

The ride-sharing service for kids are more expensive than Uber or Lyft. The cost for HopSkipDrive is $17 plus $1.50 per mile and 50 cents per minute. Zum charges $19.50 for single rides and $10 for carpool rides per child for a one-way trip.

For comparison, the Uber price estimator for the Phoenix area notes the cost for an UberX would be a base fare of 42 cents, a booking fee of $3.05 plus 85 cents per mile and 18 cents per minute.

What HopSkipDrive does to keep kids safe

Though the circumstances are different, the headline of a South Carolina college student killed after climbing into a car she believed was her Uber has some parents concerned.

But, all the apps promise safety is the first priority.

McFarland, who co-founded HopSkipDrive in 2015 with two other mothers, said it's service keeps children safe through vetted drivers, a safety team keeping watch, and allowing parents to track their child from point A to point B via their technology.

The driver verification process includes: county, state and national criminal record checks, FBI-approved finger-printing background checks, and driver's must have at least five years of care-giving experience. Most drivers are female.

The mobile app allows parents to create a code word for drivers to say when picking up the child. Drivers also wear identifiable orange shirts with "CareDriver" on the back.

If a driver is running late or experiences a flat tire, the safe ride support team will notify the parent, the school if necessary, and send a back-up driver to transport the child if needed.

"We cannot leave a child stranded," McFarland said. "We really think about safety every step of the way."

Convenient, cheaper than a babysitter

For Mesa, Ariz. parent Amanda Ohmer, it was to bring her 11-year-old daughter Emmalee to her work in Phoenix, about 30 minutes away. Her husband had a work function and she was at work so a HopSkipDrive driver transported her.

"She said it was pretty cool and she enjoyed the fact the driver was super friendly and she said it was very adult-oriented," Ohmer said. "She's a serious child, so she liked that."

The cost was $60, Ohmer said, owing to the long drive. "So not something I would do on a regular basis. But for a shorter trip? Yeah, it's convenient and probably cheaper than hiring a babysitter."

Even though Ohmer said her family lives in a safe neighborhood, the mom chose the ride-hailng service over allowing her daughter to be a latchkey kid.

"I didn't want her (home) alone for such a long stretch of time," she said.

Parents still not comfortable

Scottsdale, Ariz. parent Kathy Ariaratnam said she wouldn't say she's adamantly opposed to such a service, but background checks can't predict future behavior.

"We do gun background checks and people pass and they still go out and commit crimes. We don't live in a 'Minority Report' time," she said referring to the Tom Cruise movie where people are gifted with knowing who will commit future crimes.

The mom of an 11-year-old son said if she were to consider a ride-hailing service she would lean more toward what Bubbl offers.

The service hires only active or retired police officers, firefighters, military, nurses or other first responders. The vetting process involves in-person interviews, criminal background checks, drug tests and a motor vehicle review. The most interesting safety measures to Ariaratnam are cameras in the vehicle meant to protect the driver and passenger. Videos are deleted after the ride, and there is no live viewing, the company says.

"Technology is pretty powerful in terms of what you can track and how you can use it and how it can be used to prevent people when they know Big Brother and Big Mother is watching," she said. "I would have to ask a lot more questions before I would be comfortable."

Kid transportation services

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