8 mistakes to avoid in web app development

11 min read
October 10, 2023

Navigating the world of web app development can be tricky, and small mistakes can lead to big problems.

From development delays, and security vulnerabilities, to poor user experience due to an underperforming web app, each of these issues can greatly impact your success.

Following best practices is one thing, but actively trying to avoid mistakes is equally important.

That’s where this article comes in handy. We’ve compiled a list of eight common mistakes that are often made in web app development, and explained how you can avoid them to ensure your web app is efficient, secure, and user-friendly.

Let’s begin.

Failing to understand the target users

A crucial starting point in web app development is gaining deep insights into your target users.

After all, it’s the users you’re trying to attract and retain, and understanding their needs and preferences is paramount.

Organizations often possess a general understanding of their user base but fall short when it comes to a detailed analysis.

Some of the basic steps you might consider include the following:

  • Analyzing the user base
  • Conducting competitor analysis
  • Creating buyer personas

During this process, crucial user information, such as demographics and psychographics shouldn’t be overlooked.

Target user information

source: DECODE

Both of these types of characteristics can be crucial for developing a web app and for marketing purposes down the line.

They provide insights into common user pain points, their preferences, and expectations of a product.

Understanding the competition is equally vital. It reveals market trends, unmet needs, and opportunities to offer something distinct and superior.

A detailed buyer persona is the culmination of this in-depth analysis. It’s a comprehensive profile encapsulating the users’ needs, preferences, challenges, and behaviors.

Buyer persona

source: ThePower

This persona serves as the foundation upon which the app is built, ensuring it’s tailored to meet the specific needs and expectations of the target audience.

In conclusion, a thorough understanding of the target users is the cornerstone of developing a web app that resonates with the audience and delivers value.

Mismanaging the available resources

Another pitfall in the journey of web app development is the mismanagement of resources.

A precise timeline and budget are the lifeblood of project execution, ensuring that it unfolds smoothly and is delivered on time.

You don’t want production delays that can end up hurting your chances of success by getting on the market late.

Moreover, not accounting for the budget of your entire project is almost a guarantee of its failure.

Average web app development cost

illustration: DECODE / data: Agilie

A look at the image above reveals a stark contrast in costs associated with projects of varying complexities.

Failing to anticipate these costs beforehand can lead to budget overruns, stalled projects, and compromised web app quality.

An advanced and detailed budget plan is a safeguard against these challenges.

Factors affecting web app development costs

source: DECODE

Budgeting should include a detailed analysis of all factors influencing the cost of web app development, ensuring that every aspect is accounted for and budgeted.

But why navigate this complex terrain alone?

With DECODE at your side, the journey is less daunting.

DECODE simplifies the intricate process of estimating project timelines and budgets.

It feels like having an in-house team, characterized by close collaboration, constant communication, and a shared commitment to transforming your vision into a tangible, functional, and user-centric web app.

Overall, efficient resource management is integral to delivering a quality web app on time and within budget, and partnering with experienced allies like DECODE can be a game-changer.

Not developing a minimum viable product

In the world of web app development, it’s tempting to aim for perfection right out of the gate.

However, this approach can be a significant drain on both time and resources. The solution lies in the concept of the Minimum Viable Product (MVP).

An MVP is the most basic version of a web app, infused with essential features that make it operational and ready for user interaction.

Minimum viable product (MVP)

source: DECODE

An MVP strikes a balance.

It’s not a bare-bones prototype lacking functionality, nor is it a final product with every conceivable feature.

It’s the middle ground where core functionalities meet user accessibility, without exhausting all of your resources.

Launching with an MVP also serves as a real-time market test, offering invaluable insights into user reception and interaction, highlighting areas for improvement, and pinpointing unnecessary features.

The right way to do MVP

source: Medium

If the initial focus leans heavily towards covering all functionalities and then enhancing app reliability and usability, the project could get stuck in a perpetual development cycle.

Instead, the MVP zeroes in on the essentials.

It lays down the core, allowing the product to be built upon, refined, and enhanced iteratively, in line with user feedback.

So, an MVP is a strategic way to ensure that a web app is market-tested and the final product is both feature-rich and approved by your user base.

Adding too many unnecessary features

There’s an allure to adding a plethora of features to a web app, especially when each one seems valuable.

However, this can often lead to an overcrowded and complex application.

The graph below exemplifies how user interaction with various features usually pans out post-launch.

User interaction with app features

source: Intercom

Instead of focusing on putting as many features in an app as possible, your objective should be to hone in on features that are most likely to go in the last column, especially those at the top right corner—features that are universally used and add significant value to your product.

Starting the development with a focus on essentials ensures the app is streamlined, user-friendly, and value-driven.

A minimalist approach can ensure that the core purpose of the app is not lost in a sea of features.

One pathway to this lean yet effective approach is feature-driven development.

Feature-driven development diagram

source: Lucidchart

As illustrated, this methodology is about developing small, manageable sets of features in short iterations.

The process ensures that the app grows consistently, with each feature being a response to identified user needs and market demands, rather than adding features based on guesses.

All in all, a focus on essential features ensures that a web app remains user-centric and adaptable, ready to evolve in step with user expectations and market trends, ensuring long-term relevance and success.

Relying on too many third-party libraries

Incorporating third-party libraries during development is a common practice, as it simplifies the process and can be a great time-saver.

But, overreliance on these tools can be a critical mistake.

The answer snippet from a Stack Exchange question shown below shows the general sentiment towards using libraries.

Stack exchange libraries snippet

source: Stack Exchange

We agree that libraries can save developers from doing unnecessary work and streamline the web app development process.

However, too much dependency on these external resources can become a pitfall.

It’s a double-edged sword. While third-party libraries offer efficiency and speed, overlooking potential security implications can be hazardous.

Take a look at HubSpot’s research that reveals a concerning statistic.

Third-party libraries vulnerabilities

illustration: DECODE / data: Hubspot

More than a third of all the libraries examined were fraught with known vulnerabilities.

Alarmingly, 26% of the most frequently downloaded ones were also susceptible to exploits.

This data underscores the necessity of rigorously vetting any library before implementing it.

How to choose the right library

source: Scalable Path

Every library should be assessed for its security integrity, update frequency, and community trust.

A high rating, regular updates, and the appropriate licenses are some benchmarks to consider during this evaluation.

In essence, it’s about striking a balance—leveraging the efficiency of third-party libraries without compromising the security and integrity of the web app.

Forgetting to implement input validation

Let’s now turn to another common mistake that is often overlooked.

We’re talking about failing to implement input validation in web apps.

Omitting these vital components can affect the quality of data you collect from users while opening you up to security issues.

Web app input validation

source: WeCodeYourSite

The above screenshot showing multiple validation errors is a common sight and illustrates the immediate feedback mechanism enabled by input validation.

Beyond ensuring correct data formatting and structure, it’s a frontline defense against a range of security threats.

Web app input validation types

illustration: DECODE

In fact, without implementing the different types of validation outlined above, you are vulnerable to various attacks like injection attacks.

Without something in place to stop them, attackers can insert malicious code or scripts into a web app, manipulating it to get sensitive information or even unauthorized access.

Web app input validation error types

source: ResearchGate

Developers should ensure rigorous validation protocols, particularly for sensitive information like payment details or personal data.

While less critical validation errors might afford some flexibility and can be ignored, a failed validation should be non-negotiable when critical errors occur.

As you can see, implementing comprehensive input validation is integral to ensuring data integrity and security, serving as a robust defense mechanism against various cyber threats.

Neglecting to perform unit testing

Web app developers easily fall into the trap of assuming that meticulous development can negate the need for extensive testing.

This, however, is a grave error.

Every app, no matter how expertly developed, must be rigorously tested. Unit testing is often the first step.

Unit testing

source: DECODE

This testing practice involves testing individual units or components of a web app to validate that each part is working as intended.

Not only does this process confirm the functionality of individual units, but it also aids in the early identification of potential issues, reducing the downstream workload of troubleshooting and refinements.

Unit test life cycle

source: Katalon

The diagram above walks us through the typical life cycle of unit testing. It’s a process of executing tests, identifying defects, making necessary adjustments, and then retesting.

This iterative process ensures that the product is thoroughly refined before it hits the market.

Every web app is a complex ecosystem of interdependent components.

Unit testing ensures that each piece of this intricate puzzle not only stands up individually but also seamlessly integrates to form a robust and reliable whole.

So, this practice is non-negotiable, as it can pave the way for an error-free, robust, and dependable web app.

Failing to plan for poor internet connectivity

Finally, an often overlooked aspect of the development phase is the internet connectivity environment in which the app will be deployed.

Developers, enveloped in a bubble of high-speed internet, sometimes forget a significant portion of users aren’t as fortunate.

This oversight can lead to a web app that demands high bandwidth, performing optimally in only a select few countries shown below but faltering in areas with less stellar internet.

Fastest broadband internet by country

source: Ookla

The challenge then becomes optimizing the app to be lean and efficient, ensuring usability across diverse internet landscapes.

Some practical steps to optimize app bandwidth usage include the following:

  • Lowering image size and resolution
  • Server-side HTTP compression
  • Minifying CSS and JavaScript

For example, code minifying is a technique where all unnecessary characters from the source code are removed without changing its functionality.

Code minifying

source: CheezyCode

In the illustration above, you can see how JavaScript minification works and its effect on the code size.

Even if it might not seem much at a glance, in the grand scheme of things, every byte saved contributes to enhanced accessibility and performance.

As a result, users in areas with limited internet aren’t sidelined—they too can access and enjoy the web app without a hitch.

In conclusion, designing with the global user in mind, and not just those with premium, high-speed internet, is not just an act of inclusivity but a strategic move to widen your user base.


And there you have it.

In this article, we’ve unveiled eight common mistakes in web app development and offered insights to avoid them.

Our goal was to sufficiently prepare you to navigate these challenges.

You can now follow this advice and help enhance the quality and security of your web apps.

Or, you might want to consider taking some time to find the right development team that can do all of this for you.

The dedicated web app development teams at DECODE are always ready to assist in bringing your most ambitious web app projects to life, error-free.

Give our teams a try and schedule a consultation today.

Written by

Tarek Saghir

JS Team Lead

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