What is Application Integration? Definition and Examples


As the world progresses towards digitization, more businesses start using online tools and software solutions for automation and analysis. There always comes a moment when a team uses so many different applications that it’s time to create one unified infrastructure that enables smooth communication between them.

The Essence of Application Integration

Application integration is a process that allows independently developed applications to work together. The software that can be integrated includes desktop software, web applications, cloud solutions, mobile apps, tablet applications, and more.

A business might consider performing application integration for various reasons:

  • Better access management for the whole infrastructure
  • Improved flow of functions performed by separate tools and applications
  • Reduced time for switching between activities and applications
  • Seamless knowledge transfer
  • Better consistency of data in different sources

Application integration allows businesses to achieve a new level of connectivity and dive deeper into business processes, as integrated applications also mean integrated data for analysis.


Application Programming Interface

Application integration is done via an Application Programming Interface (API), a code instruction specifying how applications and data should interact. Apart from connecting already developed applications, API is essential to the software development process, as many modern applications have microservices-based architecture. It allows software parts to be developed independently and later connected through APIs.

Software engineers use API in their code all the time when they develop complex solutions. There’s no need to always develop an API from scratch, as there are a variety of open third-party API solutions. Connecting applications via an API is not easy; every integration project should go through almost the same steps as a software development project: planning, design, implementation, and testing.

Applications should be integrated securely, protecting the infrastructure from unauthorized access. API is often the weakest part of the system, and many system breaches happen due to the insecure API. Hackers are well aware of this, and the number of attacks on API increases each year. According to Salt Labs, there has been a 400% increase in API attackers in the last six months.

APIs also have to be usable both for end users and developers, reliable and scalable, as well as have minimal downtime. It goes without saying that a reliable API requires thorough testing before it can be implemented.

Application integration methods

There are two most common approaches to API architecture: SOAP and REST. Let’s take a look at the difference between them.

  • Simple Object Access Protocol (SOAP) is a strict instruction that works with HTTP, UDP, and SMTP protocols; it requires detailed API contracts and doesn’t cash data. It is often used to integrate legacy applications and software that needs to comply with high security (e.g., payment gateways and banking systems).
  • Representational State Transfer (REST) is a more flexible protocol used in most API projects. It works with HTTP only and is used for integrating web and mobile applications. Unlike SOAP, it can work with different data formats and boasts better scalability and performance.

In other words, you are better off choosing REST if your application requires flexibility or needs to interact with different kinds of data and online services.


Scenarios of application integration

In order to help you better understand application integration from a business perspective, we have gathered some real-life scenarios where application integration was necessary.

Real-life Example 1. A chain of hospitals Pill&Syrup hired several IT companies to develop an electronic health record (EHR) system, a remote patient monitoring system, and In Vitro diagnostics software. As Pill&Syrup had to ensure that their data management process complies with HIPAA regulations, they integrated all four applications before implementation. This way Pill&Syrup could guarantee that only those who treat the patient have access to the patient’s records and treatments.

Real-life Example 2. A marketing agency Bright Future uses various tools to promote their customers’ websites: website traffic analytics, SEO tools, Google Sheets, applications for creating design and layout, and website development tools like WordPress and others. They are also using a Dynamics CRM to manage client interactions and have relevant data for analysis. As switching between all these tools became inefficient, Bright Future decided to opt for application integration.

Real-life Example 3.

A startup RiskWisely is planning to launch its risk analysis software product on the US market. They want the app to have some pretty sophisticated AI functionality which requires a lot of time and money if developed and trained from scratch. As meeting the timeline of 6 months is critical in their case, RiskWisely decided to integrate an existing AI solution into their app to avoid overspending and time delays.


Application integration is a great tool that allows independently designed software to work as one solution. It can reduce time-to-market for startups and streamline workflows for enterprises. Modern software architecture relies heavily on APIs due to convenience and scalability. Overall, application integration can be a powerful tool if used wisely.