Rapid Application Development (RAD): An Ultimate Guide for 2024

What is Rapid Application Development?

Rapid application development (or RAD, for short) is a more adaptive approach to software development. While regular plan-based methods require a rigid structure with specific requirements, a RAD approach is based around flexibility and the ability to adapt alongside new knowledge.

In the 1970s and 1980s, the Waterfall model was the prevalent approach to software development. This method breaks down a project into a sequential map of various steps, where each step feeds from—and thus, relies on the completion of—the previous phase. A rigid approach like the Waterfall model is intuitive when it comes to engineering fields such as construction, but is insufficient when it comes to software development in a fast-paced environment.

A plan-driven process may not be the answer if you expect to iterate and adapt based on feedback during the creative process, however. A project driven by a rapid application development model is more adaptable and flexible, and can easily incorporate any feedback received into further development.

Effectively, RAD puts emphasis on the design process and the knowledge that could be gained from it. As a result, building basic prototypes and incorporating the users in the design process are crucial steps in a RAD approach. Thus, unlike the Waterfall model, the end user is tuned in to the entire process rather than only at the beginning and end. Through consistent testing and tweaking, RAD aims to deliver a product that more closely resembles the user’s needs.

Rapid Application Development Methodology

• Outlining requirements: In the first phase, all the relevant members (managers, IT staff, users, etc.) plan and agree on the project’s needs, scope, challenges, and requirements. What makes RAD different from other models in this regard is that it sets broad requirements to stay flexible over time.
• User Design & Input (Prototype, Test, Refine): In this phase, the users work with developers to create and develop one or more prototypes that cover the outlined system requirements. This is a continuous phase wherein the users interact with the prototype and provide feedback until a true final product is approved.
• Construction: This is the other continuous phase and works hand-in-hand with user input. This step focuses on implementing the feedback provided by the users through coding, testing, and any other applicable development tasks. The 2nd and 3rd phases feed into each other until the users approve the product.
• Finalization: Once the product is eventually approved, developers put some finishing touches in the form of testing, conversion, interface, or user training. Once the product is properly assessed for factors like stability and longevity, it is ready to be delivered.

Advantages and Disadvantages of Rapid Application Development

Advantages

Due to its flexibility and adaptability to new inputs, a RAD approach carries far less risk than a basic plan-based method. With an early prototype, it is fairly easy to identify any key challenges associated with the project. As such, RAD weeds out any potential problems early on in the life-cycle, making it cheaper and easier to address during development. As a direct result, RAD projects typically take a shorter time to complete.

Similarly, using and assessing a prototype while in the development process allows users to give feedback and identify possible changes more effectively. Rather than planning ahead to the final result (as with a basic Waterfall model), users can tweak and adapt the prototype to address any feedback and observations. To an extent, this makes RAD a cyclical approach, with the product’s evolution running hand-in-hand with user experience.

With a continuous stream of feedback and user interaction, a project developed with a RAD model can be more applicable and easier to implement in a business environment. Since the software changes based on the users, the resulting product is more likely to be appreciated by the end users and offer user-friendly functionality.

Finally, RAD approaches make it easier to deal with any budgetary drawbacks. Due to its flexibility and incremental nature, a RAD method allows developers to identify and tackle monetary and technical issues faster and react accordingly. Compared to a Waterfall approach, the risk of any large-scale failures is drastically lower.

Disadvantages

There are some key drawbacks when it comes to RAD approaches, as the flexibility and user functionality come with some trade-offs. Firstly, the emphasis on user experience and feedback could in effect deemphasize non-functional requirements (or NFRs) in the development process. To put it simply, focusing on improving what the software does (functional) might neglect the system’s architecture (non-functional) and overall structure. While NFRs aren’t visible to an end user, they are important for a software’s longevity.

To properly utilize a RAD approach, a project needs to fit within certain constraints as well. For one, any project that cannot be modularized is a poor fit for RAD; in a similar vein, large-scale projects simply require too much control and planning for a RAD method. Because of its looser emphasis on planning, software developed with RAD could end up poorly-designed, since making small changes consistently could upend the overall design and structure.

On top of that, RAD requires users to test the prototype throughout the entirety of the life-cycle. If the number of users or their feedback is scarce or unhelpful, a project could find itself at a standstill. In sacrificing control for flexibility, RAD depends on a reliable and helpful base of users to move a product forward.

What is the Rapid Application Development Life-cycle?

RAD takes heavy inspiration from the systems development life cycle (or SDLC, for short), and the four stages of RAD could even be seen as a condensed version of the SDLC. The stages are, roughly, as follows:

Planning

The initial stage where factors such as the project’s requirements, scope, and feasibility are assessed.

Analysis

The goal in this stage is to examine the situation and project goals in order to identify what needs to be created.

Design

Here, a rough outline of the project is created in more detail (often with numerous flow diagrams), considering details such as screen layout, features, and program rules.

Implementation/Environments

In this part of the cycle, the product is taken through various stages of development, up until it is ready for the end user.

Testing

In this stage, the software is tested on various levels to ensure the system’s readiness.

Evaluation/Maintanance

After training and transitionary periods, the software is maintained and regularly evaluated to assess any shortcomings or potential improvements.

How Сreatio Can Boost Your Development Efforts

Rapid application development tools are solutions that incorporate an integrated development environment along with traditional coding to enhance and speed up the development process. Creatio is one such solution, allowing even those with limited coding experience to develop their RAD project in mere minutes.

Creatio’s effectiveness as a RAD solution is rooted in its low-code tools; this intuitive and user-friendly platform enables anyone from the marketing, sales, service, and operations teams to tune in to the development process. These low-code tools can accelerate projects by keeping things simple company-wide—bringing applications to market quickly and effectively.

Discover the speed and efficiency of RAD with Creatio

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How is RAD Different from Agile?

Rapid application development and Agile are both terms used to describe an iterative process of software development. Either method aims to tackle the issues that traditional development methods—like a Waterfall approach—are prone to have. While the two terms are often used interchangeably, there are some subtle differences between them.

“Agile software development” came to prominence thanks to the Manifesto for Agile Software Development, a short list of essential principles and guiding values for agile development. In short, they largely coincide with RAD; an iterative design process, regular contact with customers/users, and welcoming changes in requirements are just a few commonalities between them.

However, rapid application development differs slightly from Agile development when it comes to the software itself. While regular inputs from users is one of the key features in Agile, the process nonetheless retains a focus on solid system architecture and design. Essentially, Agile development strives to achieve the same iterative flexibility as RAD without sacrificing any sustainability or technical excellence.

When is a Rapid Application Development Approach Suitable?

In short, there are a few requirements and a few situational factors that could lead you to choose RAD over other methods. Perhaps the most crucial requirement, though, is having a reliable and sizable pool of users that can test your product and provide feedback. Without enough concrete user input, a project can quickly become stagnant, taking the “Rapid” out of RAD.

Similarly, RAD requires a competent base of developers to quickly and effectively implement the changes users want to see. If you don’t have the staff for a successful RAD project, it would make sense to hire talented developers to see the product over the line; of course, this option could get expensive down the line. Either way, the process depends heavily on timely tweaks and consistent results, so having the proper staff is crucial.

Alternatively, if you simply need a project done quickly with little initial planning, RAD might be an enticing choice. Of course, the aforementioned constraints are still in play, but if they’re not an issue, approaching a project with rapid application development could produce the fastest results.

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