7 Key Steps for Good App Requirements

Let me share something that might surprise you: the most expensive bugs in software development aren't the ones you find during testing. They're the ones baked into your requirements from day one. A study by IBM found that fixing a bug found during requirements analysis costs about 6 times less than fixing the same bug in implementation, and a staggering 100 times less than fixing it after deployment.

I've seen companies spend millions on applications that nobody uses because the requirements missed the mark. I've also seen small teams build transformative software on modest budgets because they invested time in understanding what they really needed. The difference isn't talent or budget — it's discipline in the requirements process.

Whether you're building your first mobile app or modernizing an enterprise system, these seven steps will help you create requirements that lead to software people actually want to use. Let's dive in.

Here's a conversation I have at least once a month: A business leader comes to me and says, "We need an app that does X, Y, and Z." When I ask why, they often can't articulate the underlying business problem they're trying to solve. They've jumped straight to the solution without fully understanding the problem.

Before writing a single requirement, you need to clearly articulate the problem you're solving. Ask yourself: What pain point exists today? Who experiences this pain? What happens if we don't solve it? What does success look like?

A well-defined problem statement might look like this: "Our field technicians spend an average of 45 minutes per service call on paperwork. This administrative burden reduces the number of jobs they can complete by 30%, directly impacting revenue and customer satisfaction scores."

Notice how this statement is specific, measurable, and ties directly to business outcomes. It doesn't prescribe a solution — that comes later. This problem-first approach keeps your requirements focused on what matters and gives you a clear way to measure success when the app is built.

One of the most common requirements failures I see is building an app that satisfies the person who commissioned it but ignores the people who'll actually use it. Your stakeholders aren't just executives and project sponsors — they're everyone who'll interact with or be affected by your application.

Start by mapping your stakeholder ecosystem. Who are the end users? Different user types might have different needs. Who manages the system? IT teams often have requirements around security, maintenance, and integration. Who benefits from the data? Business analysts and leadership might need reporting capabilities. Who's affected by process changes? An app that changes workflows affects people beyond direct users.

Once you've identified your stakeholders, engage them meaningfully. Don't just send a survey — have real conversations. Shadow them in their work environment. Watch how they currently solve the problem you're trying to address. Often, the most valuable requirements come from observing workarounds that users have developed to cope with inadequate tools.

I once worked on an inventory management system where we nearly missed a critical requirement because we didn't talk to warehouse workers. They had developed an informal system of Post-it notes and hand signals that was faster than the existing software. By incorporating elements of their workaround into the new app, we created something they actually wanted to use.

Every requirements session I've ever facilitated has produced a wish list that would take years to build. That's natural — once people start thinking about possibilities, ideas flow freely. Your job is to separate the essential from the nice-to-have.

I use a simple but effective framework called MoSCoW prioritization: Must have (critical for the app to function), Should have (important but not essential for launch), Could have (desirable if time and budget permit), and Won't have (explicitly out of scope for now).

The key word here is "for now." Requirements that fall into "Won't have" aren't rejected forever — they're deferred. This acknowledges the stakeholder's input while keeping the current scope manageable. Document these deferred requirements; they often form the basis for future releases.

Be ruthless about the "Must have" category. A requirement only qualifies if the app genuinely cannot launch without it. I often ask stakeholders: "If this feature wasn't included, would you refuse to use the app?" If the answer is no, it's not a must-have.

This prioritization also helps when budget or timeline constraints inevitably arise. Instead of cutting features arbitrarily or compromising quality, you have a pre-agreed hierarchy that guides decisions.

Vague requirements are the enemy of successful projects. "The system should be fast" is not a requirement — it's an aspiration. "The system should return search results within 2 seconds for queries of up to 1,000 records" is a requirement you can actually build and test against.

Good requirements share three characteristics. First, they are clear and unambiguous. Anyone reading the requirement should understand it the same way. Avoid jargon, define terms, and be specific about numbers, dates, and conditions. Second, they are testable and verifiable. You should be able to create a test that definitively proves whether the requirement has been met. If you can't test it, you can't verify it was built correctly. Third, they are traceable. Each requirement should link back to a business need and forward to design decisions and test cases. This traceability helps you understand why each requirement exists and ensures nothing gets lost in translation.

I recommend using a consistent template for documenting requirements. Include a unique identifier for tracking, a clear statement of what the system should do, the business rationale explaining why this is needed, acceptance criteria defining how you'll know it's complete, the priority level (Must/Should/Could), and dependencies noting what other requirements this relates to.

This structured approach might feel bureaucratic for small projects, but I've seen it save countless hours of confusion and rework, even on modest initiatives.

Most stakeholders naturally think about functional requirements — what the app should do. But non-functional requirements — how well the app should do it — often determine whether users actually adopt the application.

Non-functional requirements span several categories. Performance includes response times, throughput, and resource usage. Security covers authentication, authorization, data encryption, and compliance requirements. Reliability encompasses uptime expectations, failure handling, and data backup. Usability addresses accessibility standards, device support, and user experience considerations. Scalability involves growth projections and how the system should handle increased load. Maintainability concerns code quality, documentation, and ease of updates.

I've seen applications that met every functional requirement fail because they were too slow, didn't work on mobile devices, or couldn't handle the user volume. These "quality attributes" are often harder to retrofit than features, so it's essential to capture them upfront.

When documenting non-functional requirements, be as specific as possible. "The app should be secure" is meaningless. "The app should encrypt all data in transit using TLS 1.3 and at rest using AES-256, and should pass OWASP Top 10 vulnerability testing" is a requirement you can actually implement and verify.

Requirements aren't something you finalize once and forget. They need continuous validation throughout the project. The earlier you catch a requirements error, the cheaper it is to fix.

Start with peer reviews. Have stakeholders review each other's requirements. The marketing team might spot assumptions in sales requirements, and vice versa. These cross-functional reviews often surface conflicts and gaps that would otherwise emerge during development.

Create prototypes and mockups early. Modern tools make it easy to build clickable prototypes that let stakeholders experience the proposed solution before a single line of code is written. I've had requirements completely rewritten after stakeholders interacted with a prototype — not because the requirements were wrong, but because seeing them come to life revealed better approaches.

Walk through scenarios. Take key use cases and trace them through your requirements. Does the flow make sense? Are there gaps? What happens in edge cases? This scenario-based validation often reveals implicit assumptions that need to be made explicit.

Finally, build feedback loops into your development process. Agile methodologies excel here — regular demos and sprint reviews let stakeholders validate that what's being built matches what was envisioned. Requirements can and should evolve as you learn more, but through a controlled change process, not chaotic scope creep.

Here's an uncomfortable truth: no matter how thorough your requirements process, things will change. Markets shift, regulations evolve, users discover new needs, and technology advances. The question isn't whether your requirements will change, but how well you can adapt when they do.

Establish a change control process from the start. This doesn't have to be bureaucratic — for small projects, it might be as simple as documenting changes in a shared log and getting sign-off from key stakeholders. For larger initiatives, you'll want a formal change request process with impact analysis.

Maintain version control for your requirements documents. When changes occur, you need to understand what changed, why, and what was affected. This history becomes invaluable when debugging issues or planning future releases.

Build flexibility into your architecture. Modern approaches like microservices, API-first design, and low-code platforms make it easier to adapt to changing requirements without massive rewrites. When evaluating technical approaches, consider not just today's requirements but how easily you can accommodate tomorrow's.

Most importantly, maintain ongoing relationships with your stakeholders. Requirements gathering isn't a one-time event at the project's start — it's a continuous conversation throughout the application's lifecycle.

Bringing It All Together

Good requirements are the foundation of successful applications. They align stakeholders, guide development, and provide the criteria for measuring success. But creating them is as much art as science — it requires technical understanding, communication skills, and business acumen.

The seven steps we've discussed — starting with the problem, engaging stakeholders, prioritizing needs, writing clear requirements, capturing non-functional needs, validating continuously, and planning for change — provide a framework that works across industries and project sizes.

Remember that perfect requirements don't exist. The goal isn't perfection; it's reducing uncertainty enough to build something valuable. Every hour spent on requirements analysis typically saves many more hours in development and prevents the costly rework that comes from building the wrong thing.

If there's one thing I hope you take away from this article, it's this: invest in your requirements process. It's not glamorous work, and it can feel like it's slowing you down when you're eager to start building. But I've never seen a project fail because it spent too much time on requirements. I've seen plenty fail because they spent too little.