When to Create an App: Safety Beginners Can't Ignore

The question "should I build an app?" It is almost always accompanied by cost sheets, canvas ideas and dreams of growth. It is rarely accompanied by a question as important as: "am I prepared to save the data of the people who will use it?".

This absence is not evil. It's ignorance. Those who are starting out see security as something that will be resolved later, when the product grows. But security is not a feature that is added at the end, it is a foundation. And you don't add a foundation to the building already built.

This text is for anyone who is deciding to create an app and wants to understand, without jargon, what needs to be in their head from day one. Not to become an expert, but to avoid making costly decisions down the road.

Why security matters even before code

Every application that does something useful stores data. Name, email, telephone, location, usage history, sometimes document and payment details. The moment you collect a person's first data, you have assumed a legal and ethical responsibility.

In Brazil, this has a name: LGPD, the General Data Protection Law. It is not a suggestion. It defines that you are responsible for the data you collect, that you need a legal basis to collect it, and that you need to protect it. A startup app and a large enterprise app are subject to the same law.

The practical consequence: you don't decide whether to worry about security. You only decide whether you will worry before or after the problem. And then it is always more expensive, in money, in reputation and, sometimes, in fines.

The thesis: security is an architectural decision, not a maintenance one

The central idea of this article is simple. Security is not a layer that you put on top of the finished product. It is a set of decisions that shape how the product is built from the beginning.

Where the data is stored. How passwords are handled. Who can see what. How the application talks to the server. Each of these choices is made early, and remaking them later means rewriting entire parts of the system.

That's why the best time for a beginner to think about security is not when they are already advanced. It's right now, at the beginning, when decisions are still cheap to make.

The fundamentals no one should skip

You don't need to master cryptography to start responsibly. It needs to respect a handful of principles that resolve most initial risks.

Never store password in plain text

Passwords should never be saved as the user typed them. They go through a process called hash, which transforms them into something irreversible. Even if someone steals the database, they cannot read the passwords. Modern frameworks already do this for you, the beginner's mistake is to disable or bypass this protection in a hurry.

Put authentication and authorization in place from the beginning

Authentication is confirming who the person is. Authorization is defining what it can do. Both are different and both matter. A common mistake is to protect the login screen but forget to check, in each action, whether that user has permission to do that. The result is the classic: changing a number in the URL and accessing someone else's data.

All communication must be encrypted

Data traveling between the application and the server must travel protected, using HTTPS. Without this, anyone on a shared network, a cafe Wi-Fi, for example, can intercept what is being sent. Today this is standard and cheap. There is no excuse not to do it.

Collect only what you need

The safest data is what you don't keep. Before asking for information, ask: do I really need this? Collecting everything "because it might be useful one day" increases what you have to protect and your risk in the face of LGPD. Data minimization is, at the same time, a good security practice and a legal requirement.

A concrete example: the app that was leaked without being hacked

Imagine a small scheduling app created by a budding entrepreneur. It works well, grows, gains users. One day, someone discovers that, by changing the identification number on the request, they can see the appointments of any other customer, including name, telephone number and address.

There was no sophisticated invasion. There was no genius hacker. There was an authorization failure: the system confirmed who you were, but did not verify whether that data was yours. It is one of the most common flaws that exist, cataloged by OWASP among the main application risks.

The lesson for the beginner: most leaks don't come from cinema attacks. It comes from basic oversights that could have been avoided with simple principles applied from the beginning.

Use what already exists instead of inventing

There is an understandable instinct in those who start: wanting to build everything from scratch to understand how it works. In security, this instinct is dangerous. Cryptography, password management, and authentication are areas where even experts make mistakes, and where a subtle error opens up a huge hole.

The responsible path for the beginner is to use consolidated libraries and services, maintained by communities that have already faced and fixed the problems you can't even imagine. Don't write your own password algorithm. Don't invent your own login scheme. Use what has been tested by thousands of people and is updated when a failure appears.

This also applies to keeping dependencies updated. Most attacks exploit flaws that are already known and have already been corrected in newer versions, which the victim simply did not install. Upgrading is one of the cheapest and most overlooked defenses out there.

The reflection that separates amateur from professional

There is a dangerous mental trap: "my app is too small to be targeted." It's exactly the opposite. Small apps often have the weakest protections, making them easy targets for automated attacks that scan the internet looking for known flaws. No one needs to specifically want to attack you, all it takes is for a robot to find the door open.

Maturity here is not technical, it is posture. It's understanding that, when asking for someone's data, you made a promise to care. Breaking that promise, even unintentionally, has real consequences for real people.

And there's one point in business that beginners underestimate: trust is the hardest asset to rebuild. A product can recover from a functionality failure. Recovering from a breach that exposed customers is much more difficult.

Start simple, but start right

You don't need a fortress to launch your first app. It needs solid fundamentals: protected passwords, encrypted communication, verified authorization, and minimal data collection. This already puts you ahead of a huge number of products on the market.

Security for beginners is not about knowing everything. It's about not making the mistakes you know how to avoid. The rest can be learned over time, as long as the foundation is right.

If you are about to create an application and want to understand how to build security by design, there are other articles on the blog about LGPD, authentication and secure architecture that delve deeper into each of these points. If it's a decision-making moment in your organization, it's worth discussing it before writing the first line.