Rapid application development (RAD) is a software development methodology focusing on adaptability rather than planning. RAD, as opposed to the Waterfall, emphasizes the usage of software and user input. D. Dinadasa was the first to establish and effectively deploy a development process based on RAD in the mid-1970s.
Approximately 20 years later, James Martin introduced his approach, which involved iterative development and the construction of prototypes. In general, RAD is suited – but not limited – to developing software driven by user interface requirements. It is an agile project management strategy having as main advantage a fast project turnaround, which makes it an attractive choice for developers who prefer fast-paced environments.
According to Markets and Markets, the demand for faster software development is rising due to an increased need for customized and scalable software.
Fast-paced markets and the increasing demand for innovation are expected to be the dominant force for an increased demand for rapid application development.
The main advantage of a RAD method is quick project turnaround, which makes it an appealing alternative for engineers working in a fast-paced setting such as software development. The focus of RAD on eliminating the planning stage and emphasizing prototype development allows for this quick speed.
If we compare the rapid application development process with traditional methods, we can easily conclude that the entire development process is compressed. As a result, the new application is built and delivered much sooner.
The 4 Phases of RAD
Rapid application development is equally based on the reusability of components and software development. Due to the short development cycle, the time required for application development is reduced.
The process of the RAD model includes creating a prototype and delivering it to the customer to get feedback. According to the given feedback, changes to the prototype are made. The process is repeated until the customer validates the prototype.
When creating a RAD model, there are a couple of phases to go through, including analysis, design, construction and final testing.
Phase 1: Requirements planning
The first phase, known as requirements planning, is a phase in which the information is gathered through various business-related sources.
At this point, developers, end users and team members collaborate to define project goals and aspirations, as well as potential challenges that will need to be addressed during the construction.
The following is a simple summary of this stage:
· Investigating the present issue
· Defining the project's needs
· Finalizing the criteria with the consent of each stakeholder
Phase 2. User design
The user design is the second phase of the Rapid Application Development paradigm. It entails gathering user feedback and creating many project prototypes in progress utilizing developer tools.
During this phase, clients collaborate with developers to ensure that their needs are addressed at every stage of the design process. It's similar to customizable software development in that consumers may evaluate each product prototype to guarantee it matches their expectations.
RAD developers create several prototypes with various features and functionalities rather than working with a precise set of criteria. The client(s) then assess all of these prototypes to determine what should be kept and discarded.
On average, 30% to 40% of system requirements will change during development. With prototyping, it is easier to look at the dynamic states of the system before it's built.
Phase 3. Construction
In this phase, prototypes and beta systems from the design phase are transformed into a working model.
The final software model is created much faster because all problems and necessary changes were addressed during the previous phase.
During this phase, besides functionality, feedback is provided on a range of other things, including aesthetics, interface, and so on. The prototype process then proceeds, considering all the incoming comments.
This phase can be broken down into several steps:
· Rapid construction preparation
· Development of programs and applications
· Unit, integration and system testing
This step is essential since the clients may still provide feedback. They can provide modifications, revisions, or even new ideas to tackle problems as they develop.
Phase 4. Cutover
This is the phase of implementation in which the final product is released.
The final step entails finalizing the aesthetics, features, functionality, interface and everything associated with the software product. Interfaces between the many separate components must be thoroughly tested.
· The cutover phase includes:
· Final testing
· Finished integration of client's changes and approvals
· User training before release
When compared to other development methodologies, rapid application development differs significantly. The apparent distinction is that rapid application development concentrates on faster development while keeping the product quality high. One example is a case study "Development of Delivery Management System for the Logistics Industry". In this case, our RAD platform FIYU, in combination with agile methodologies, saved two years in software development.
This methodology is focused on keeping the client/end-user involved during the development throughout all phases.
Even though RAD is already a couple of decades old, it remains relevant and continues thriving. When new products and trends disrupt entire industries, and businesses are moving faster than ever, developing and deploying new products as quickly as possible is mandatory.
Over the years, RAD has demonstrated strength in speeding up development while keeping the costs low and the quality high.