Codejig logo

Rapid Application Development vs Traditional SDLC



August 16th, 2019 Software development

Everything on earth, both living and nonliving, has a life cycle. There is a period from when it is born or created to when it dies or breaks. Its life cycle can be broken down into stages that help us to better understand the process of development.

This idea can also be applied to creating apps, and it is commonly called the Software Development Life Cycle (SDLC). From the time when the first software was created up until now, this life cycle used to take many forms. Primarily this happened due to the changing environment and, as of the 21st century, due to the digital transformation. People began to think of new and better ways to build software that will serve its intended purpose. Over this time, five primary methodologies have been developed, which are the Waterfall, V-shaped, Iterative, spiral, and Rapid application development models. All of them have a different approach to the process of app development. Developers choose which methodology to use based on the project type and its requirements.

Traditional SDLC mainly refers to the Waterfall approach since it was the first and oldest methodology to be used. The Rapid Application Development model is the latest methodology created that tried to correct the shortcomings of the older models. So, we will be comparing the newest vs. the oldest methodology.

To compare the RAD model and the traditional SDLC, we need to know how they work and their processes.

The Rapid Application Development model (RAD)

In the RAD approach, the client can review the app and give feedback after every iteration made in the process of development. This model is more practical, and the end-users are usually happy with the final product because they participate in all phases of development. Here are the stages of RAD:

  1. Planning

    At the beginning of every project there must be planning. All the parties involved have to sit down and define the project requirements. It is essential to discuss and come up with the project timeline and budget analysis.

  2. Building prototypes

    This is one of the key differences between the RAD model and the traditional SDLC. Here functional prototypes are built quickly based on the project requirements and the discussions on the planning stage. These prototypes are built so that quick changes can be made without any difficulties. Rigorous testing and iteration are also performed to make sure that the software is free of bugs.

  3. Feedback

    The prototypes are now given to the customers to use, review, and give feedback. They can suggest what features should be added or removed from the software depending on their relevance to the business processes. These steps are repeated until the customer is satisfied with the software.

  4. Deployment

    Once the tests, changes, and iterations are done and the customer is satisfied, the app is deployed or finally presented to the client. Updates and modifications can be made in the final product without much difficulties.

The traditional SDLC

With this approach, the project is planned out to the end and executed in an orderly manner. Each phase of development must be completed before the next one starts. The progress flows sequentially, going downhill like a waterfall, hence from where the name comes. Here are the stages in this methodology:

  1. Planning

    This first stage involves strict planning of the project requirements. The purpose, functions, timeline, and budget of the software are defined at this stage. Once this is done, there is no coming back to it.

  2. System design

    Once the requirements are laid out, the technical design phase begins. This stage turns the requirements into technical specifications. The specialists involved in this phase take care of the architecture, system, and hardware requirements.

  3. Implementation

    The development phase starts once the design stage is over. This is where all the coding and testing takes place.

  4. Deployment and maintenance

    Finally, once the build is complete, the application is deployed. Deployment is followed by a warranty period and a maintenance phase. This phase will see to it that the app is available, enhanced, and defects are fixed.

Now that we have seen how both methodologies work, it is time to lay out clearly all the differences between them.


The stages are not strictly defined. The stages are laid out clearly and structured sequentially.
This model is iterative and different stages of the app development can be reviewed when needed. Here, once one step is complete, it is not reviewed and iterations or changes are not made. Every phase is completed before the next one starts.
The development of apps using this model is faster because automated RAD tools and techniques are used. App development takes longer time and effort.
It is not essential to know all the requirements of the project beforehand as they can be added and changed as development is going on. All the requirements of the project must be known and laid out clearly beforehand because they cannot be changed later on.
Changes can be implemented easily. Changes are difficult to implement because of the sequential nature of the model.
This methodology relies very much on feedback from customers to build the software. Minimal customer feedback is used.
Small teams are assigned to individual modules. Modularisation is absent, and a large team is needed for the various stages of development.
This methodology is suitable for projects with a low budget and short duration. It is suitable for projects with a more extended schedule.
Components here are reusable, which helps to reduce the project’s life cycle time. Components here may not be reusable.

For building apps in this era of digital transformation where the demand for apps is skyrocketing, the RAD methodology is ideal. But no model can be ideal for all projects and it is always good to know when it is better to use which model. As to RAD, one of the best places to find the tools for building your app is at Codejig.