What’s rapid development and why is it important? 

Software development is a long process that involves multiple interactions. On average, the whole development lifecycle takes up to a few months based on the complexity and project scope. However, some solutions may require rapid development and implementation, thus calling for a shorter delivery time frame.

But is it possible to squeeze the whole development workflow in mere weeks without compromising quality? Enter rapid application development, an established software philosophy that welcomes tight deadlines and fires.

The basics of the RAD approach

Rapid application development or RAD is a delivery model that majorly relies on prototyping and iterations over a long creation process and testing. Being an umbrella term for flexible software development approaches, it prioritizes user feedback and promotes iterative deliveries based on user insights.

Typically, a RAD life cycle includes four core stages:

• Eliciting project requirements;
• Creating a prototype;
• Rapid construction and feedback gathering;
• Application upgrade and deployment.

Thus, instead of painstaking planning, RAD relies on a method of prototyping to introduce the product.

Prototype: the fundamentals

Prototyping is put at the heart of the RAD model. As such, it’s a medium to a highly detailed representation of a final product. Prototypes mimic users’ interaction with the product and allow stakeholders to have a clear vision of the outcome.

Prototyping saves time and money that would have been spent developing untested solutions. Data sharing between the interface and the backend is usually skipped to reduce costs and speed up the development process.

Prototyping: main types

Product prototypes come in different flavors. From fidelity ones to clickable prototypes, each of them is geared towards a specific goal, be it behavior testing or usability assessment. Let’s have a look at the main types of prototypes.

Wireframe prototype

These are low-fidelity representations of a screen layout that reflect the informational structure of a product. Wireframe prototypes are primarily used to plan a Minimum Viable Product or the early solution version.

Wireframe prototypes are limited to user flow and information structure to highlight the core design principles that empower the future solution. It also helps the designer to narrow their attention to the usability potential of the product.

However, wireframe prototypes are rarely used for testing purposes, although they can help gather feedback at the planning stage.

Designed prototype

This kind of prototype is more detailed and includes an early design sample. It’s a medium-fidelity prototype that is enhanced with User interface design. In this case, stakeholders have a better idea of the overall look and feel and are aware of the color schemes and other UI components.

Clickable prototypes

These high-fidelity representations offer an interactive user experience that is close to the full-fledged product. Unlike previous prototypes, a clickable one can demonstrate multiple states of the applications, including additional functionality and UI elements.

Despite the differences, these three prototype iterations aren’t mutually exclusive. Each of the steps is at the different planning stages and is useful for different kinds of testing.

The main benefit of prototypes is that they can be developed with no pre-planning hassle. They are also flexible, allowing for easy changes and product enhancements.

In this case, a client also has a clear idea of the full-throttle product at the early stage and can provide feedback faster than within a traditional development approach.

RAD model vs Waterfall

The rapid development approach isn’t a one-size-fits-all option for any project. Sometimes the RAD model can be challenged by the Waterfall methodology which is the exact opposite of the RAD. Let’s see how the two compare and which one is more suitable for your project.

Fundamentals

Unlike the flexible RAD approach, the Waterfall philosophy implies a sequential transition from one stage. It means that the development process sticks to the plan with no iterations or major changes. The transition to a new stage is only possible after the previous stage is completed.

Risk level

Since the Waterfall model is more stringent compared to the RAD one, the risk level is high. Once the functionality has been implemented, there’s no going back. Therefore, Waterfall relies on a thought-out plan that doesn’t allow for modifications.

On the contrary, the RAD model is a low-risk approach for software development that ushers in meaningful changes based on constant client feedback.

Flexibility

Waterfall project management is a type of sequential delivery model. Under this model, software development proceeds through a set of predefined stages, which are typically time-boxed or have specific deadlines. Therefore, any changes have to be ushered in early in the process. Any unplanned changes result in high development costs.

Product delivery

The Waterfall model presupposes last-mile delivery at the end of the whole lifecycle. Until the very release, the product isn’t deployed for feedback and is unavailable for the end-users. The RAD model welcomes earlier deliveries and feedback to polish the software as needed.

A RAD model’s 5 essential stages

When applying a RAD model, companies should introduce the four crucial stages. These include analysis, design, construction, and testing.

Stage 1: Analysis and requirements gathering

First and foremost, developers and stakeholders need to elicit requirements. To do that, business analysts research business needs a target audience and the market. This stage is similar to a project scoping meeting. However, it’s much more concise and fast.

The result of this stage includes the following deliverables:

• A quick, yet effective analysis of the current problem;
• Uncovering the project requirements;
• Validating and finalizing the requirements with each stakeholder.

Stage 2: User design and prototyping

This stage is the hallmark of the rapid development model. Instead of a long planning and validating process, the software development team collects users’ feedback.

Following user insights, the developers create several prototypes of the product. Once all prototypes are up and running, stakeholders choose the best ones as a final foundation for a full-fledged product.

Stage 3: Rapid construction

During this stage, developers enhance the prototypes that have been shortlisted during the previous stage.

A breakdown of this stage includes the following stages:

• Getting ready for the rapid construction;
• System design;
• Coding;
• Testing.

Despite the speed of development, this stage still offers flexibility. Stakeholders can provide input, and suggest changes and modifications.

Stage 4: The cutover

The final stage of the RAD model includes project delivery and deployment. Before the release, developers finalize the look and feel of the product. The team also performs data conversion, testing, and switchover to the new system.

The bottom line

The RAD philosophy is a long-time favorite among developer teams who want to drive value fast and efficiently. Quicker delivery, fast changes, and lower development costs are among the main benefits of the RAD philosophy. While the traditional Waterfall approach also has its place, the RAD model is more flexible and change-welcome.