The Target Corp. executive who helped birth one of the Minneapolis-based retailer’s most celebrated digital innovations is leaving the company.

Alan Wizemann, vice president of mobile and Target.com, played an instrumental role in launching Cartwheel, the retailer’s mobile coupon app that has rung up more than $1 billion in sales since it rolled out two years ago.

Cartwheel is one of the most successful retail apps in the market and has been held up within the company as an example of what Target needs to do to better compete with the likes of Amazon.

A Target spokesman declined to comment on Wizemann’s departure, noting that the company does not comment on personnel moves. Wizemann could not be reached for comment.

Wizemann came to Target a few years ago from the tech start-up world where he founded ShopIgniter, a social networking-related retail firm that was sold last year. He was initially brought in as a consultant to help salvage Cartwheel when it was still in the project stage.

As internal frustrations mounted that Cartwheel might never see the light of day under Target’s layers of bureaucracy and risk-adverse culture, Wizemann got buy-in from Target’s leaders to run the project more like a start-up. He cut the team working on it from 200 to 50 and pushed the retailer to let the team put it out in a beta form, knowing it wouldn’t be perfect and would need tweaks.

Wizemann was hired as a full-time Target employee in June 2013. But he continued to live in Portland, Ore., and make regular visits to Minneapolis and Target’s San Francisco-area offices.

“Based on his background, it wouldn’t surprise me if he decided to start a new start-up,” said Amy Koo, an analyst with Kantar Retail. “I would expect his departure might peel off a couple of other people as well.”

His exit shows how hard it can be for more conventional retailers to attract and hang on to tech talent who may be more drawn to the likes of Amazon or start-ups in Silicon Valley, she added.

“If you want to work in e-commerce, Target would not be the first place you would want to work,” she said. “Even Google has trouble hiring talented people, so it’s not an easy thing for Target to do, too.”

At the same time, Target CEO Brian Cornell, who came on board a year ago, has placed a big priority on improving Target’s online prowess. The company is planning to invest more than $1 billion this year to help beef up its digital efforts. And Target has been making big strides in this realm with online sales growing about 40 percent in each of the last two quarters. He has also been working to turn Target into a more nimble, fast-moving organization.

Meanwhile, Cartwheel itself continues to be led by Sarah Peterson, who was part of the original team.

Target’s headquarters have also been in the midst of a lot of turnover. The company has laid off more than 2,000 corporate employees so far this year. Last month, Target announced that Kathee Tesija, the retailer’s chief merchandising officer, was leaving. Wizemann reported to Tesija through Jason Goldberger, the president of Target.com.

A number of other lower-level executives have also left the company in recent months, which is not uncommon under new management. Bryan Everett, who was Target’s senior vice president of store operations, left in May and has taken a similar job at Rite Aid. And Reba Dominski, previously the retailer’s senior director of community relations, has been hired by U.S. Bancorp to be a senior executive of its foundation.