Chief information officers, on the hook to automate manual and repetitive business processes, are increasingly turning to tools designed to create applications quickly, without the sweat of writing and debugging lines of code.

Collectively known as “low-code,” these tools have been available in some form for decades. But they have grown more popular with information-technology staff and other departments as workplace automation grows and young, mobile-savvy people join the workforce.

With low-code, employees can quickly make apps by picking, dragging and dropping from a collection of ready-made software building blocks.

Johnson Controls International PLC, an Ireland-based industrial and technology conglomerate that makes heating, ventilation, and air conditioning systems, tapped nontech employees like engineers to create low-code dashboards that track installations, record project metrics and manage service calls, said Chief Information Officer Nancy Berce.

The company, which has about 105,000 employees across more than 100 countries, set up guardrails so the low-code apps don’t disrupt the resiliency of its central systems, she said.

“A lot of people are creating a lot of good things; how do we start to share that and make that more available to broader users? We haven’t quite figured that one out yet. That’s the next level of maturity,” Ms. Berce said.

Freeing up staff to focus on core technology issues was one of the reasons St. Luke’s University Health Network in Pennsylvania started using low-code, said CIO Chad Brisendine.

“There’s always a bigger appetite for IT than what we’re able to provide. I see this as helping meet that demand,” Mr. Brisendine said.

IT employees turned to low-code to build more than 20 applications using Microsoft Corp. tools. None of them took more than 20 hours to create.

It took eight hours to make an app that pulls information from the hospital’s systems, including a Workday Inc. platform, to track and send reminders to staff on continuing medical training, a requirement for doctors to retain their license. The author, an analyst in the IT department, didn’t know how to code, Mr. Brisendine said.

Mr. Brisendine next year plans to expand low-code training to more business units within St. Luke’s, which has about 15,000 employees.

Companies including Siemens AG , Appian Corp. , Pegasystems Inc. and Salesforce.com Inc. also provide low-code tools.

Forms of low-code have been around for decades, but combining it with the use of application programming interfaces, chunks of code designed to connect systems and platforms and share data, has made it easier for those not conversant in C++ or Java to create applications with a punch, said Jason Wong, senior director at research and advisory company Gartner Inc.

Gartner is projecting that low-code will account for more than 65% of application development activity by 2024.

David Hoag, CIO at Options Clearing Corp. Photo: Charlie Simokatis/Options Clearing Corp.

David Hoag, CIO at Chicago-based Options Clearing Corp., a central clearinghouse serving as a backstop for trades in the options market, said making low-code applications is as easy as dragging and dropping widgets.

The company used low-code to develop a visitor-registration system as part of an “app a day” program, where technology teams work with other departments to create applications to solve pressing business problems. The system, created in less than a day, registers visitors, logs arrival and departure times, captures visitor and badge information, and helps the facilities team generate reports on visitor activity.

Similar commercial software was quoted at costing between $30,000 and $50,000 a year, Mr. Hoag said.

OCC started building low-code apps in 2015 and today uses about 30 of them. Mr. Hoag sees low-code’s use spreading beyond IT.

“More people will be entering the workforce who have the foundational skills necessary to run with these things. Even if they’re not Java and HTML and JavaScript experts, they’ll be able to implement low-code systems,” Mr. Hoag said.

Write to Agam Shah at agam.shah@wsj.com