Parenthood comes with many challenges and frustrations, but two Philadelphia residents have created an app to eliminate one: shopping for kids' shoes.

Eve Ackerley and Carolyn Horner on Wednesday launched Jenzy, an app that allows parents to size their kids' feet and buy shoes for them without a trip to a shoe store. Horner said the idea started as an app for adult shoe-shopping, but the two reevaluated their plan after Horner's unsuccessful trip to the shoe store with her young nieces.

After some research, they realized it was often more difficult for parents to buy shoes for their children than for themselves. Ackerley said the cofounders learned that 70 percent of kids are wearing the wrong size shoe because of growth spurts and improper sizing.

"So often, apps get built and they're not really solving a problem, and we really, really wanted to solve a problem with Jenzy," Horner said.

Ackerley and Horner started reaching out to moms to discover the most common concerns parents have about shopping for kids' shoes. After realizing how much sizing variability there is between shoe brands, they committed to start with a focus on shoes for kids up to six years old to ensure the most accurate fit possible.

Ackerley said she and Horner spent over a year beta testing the app with around 300 moms, which allowed them to streamline the process and make it as user-friendly as possible. The app is able to measure foot size by using the smartphone's camera to compare the child's foot with a standard credit card.

Beta testing also exposed them to a gap in the shoe-shopping market. Other sizing apps are aimed at adults, and sales sites such as Zappos and Amazon don't offer a sizing feature.

South Philadelphia native Danielle Fike, who started beta testing Jenzy with the first version of the app, has a 6-year-old son and twin 3-year-olds — a boy and a girl — so she prefers online shopping to taking her kids to a store. Fike said she enjoys using Jenzy not only because the product is now "seamless," but also because "they have really great, high-quality shoes" in a curated selection.

The company has partnered with 12 kid shoe brands, Ackerley said. She said Boston-based company Morgan & Milo was one of the first to work with Jenzy, helping them perfect the app's sizing algorithm and providing certain shoe styles for sale through the app.

"They were looking for brands that had a focus on fit and function," said Mia Abbruzzese, founder of Morgan & Milo. She said her company also appealed to Ackerley and Horner because their shoes aren't "overly-distributed."

Robert Moore, cofounder and CEO of intelligence platform Crossbeam, first encountered Jenzy through his role as board president of Philadelphia Start-up Leaders, a nonprofit that provides mentoring for start-ups in the Greater Philadelphia Area. He said the app "fits perfectly into the paradigm of modern e-commerce" by providing a curated selection of shoes and "using the app itself to make some decisions."

"By going in and actually taking much more detailed measurements, they're able to have a refined view of precisely what fit [a child's] needs," he said.

Since the app launched in the Apple app store on Wednesday, Ackerley said 100 people have downloaded Jenzy, and about half have completed the sizing process. Jenzy is a two-person operation right now, Horner said, but she and Ackerley are aiming to add more staff members, shoe sales partners, and shoe styles to the company by the end of the fall.

While they have plans to expand, Horner said she is happy they decided to start small to offer users the most accurate sizing and best products possible. Jenzy has sold 50 pairs over the past six months of beta testing with only three returns for incorrect shoe size.

"We were [originally] focused on kids all the way up to 13 or 14 years old," she said. "We cut back and said we're only going to be focused on kids zero to six, and we're only going to sell — right now we have 55 shoes in our inventory. But we are confident with how to fit them and confident that they're good kid shoes, too."