In the initial phase, designers, developers and users make a rough agreement on the scope of the project and prioritize the application requirements so that prototyping can be started in the future phases. In the first phase, both developers and users are allowed to talk and communicate with each other. In the subsequent phases it will be omitted.
Based on the list of application requirements with prioritization, the developers design an executable prototype of the software as soon as possible. They can use a “software kit” to quickly assemble the most important basic requirements.
In the second phase, feedback from users is collected after completion of the first prototype. The focus is on defining the system architecture. Requirements are supplemented or refined. This makes it possible to create initial modelling. This step is repeated as often as necessary to further develop the project. In contrast to the first, the second phase serves more for a user’s monologue.
Once the basic user and system design has started, most of the actual application coding, testing and integration takes place in the design phase. Together with the user design, the construction phase is repeated as often as necessary because new components are needed or changes are made to meet the project’s requirements. The user’s new requirements are optimized and added to the software in a short development cycle, usually between one day and up to three weeks. This approach creates new and improved versions of the software in every iteration.
The final phase, the cutover, allows the development team to move the components into a live production environment where all necessary tests or team training can be carried out.
Due to the cyclical process, Rapid Application Development differs significantly from the waterfall model. In the classic waterfall model, each phase of development forms an independent unit. After completion of each unit, the next step is considered. As with a waterfall, it is no longer possible to return to a previous phase.
In contrast to the Rapid Application Development approach, this allows each step in the waterfall modernization process an enormous amount of time to avoid errors. As a result, software development is slower and takes a lot of time and energy to develop. Errors in development or incorrect requirements can quickly make a project fail in the waterfall model.