The Ultimate Guide to the Web & Mobile App Design

How to design an app

Every one of us uses many mobile apps daily. We all send messages, share photos on social media, check public transport itineraries, or shop. The competition on the market is high, but according to the stats, mobile usage and the number of mobile apps downloaded increase yearly.

How to design a perfect app? The one that will attract users and make them stay for longer? An app that will be your company’s source of income and higher revenue? Are there any useful app design tips?

In this article, I’ll guide you through the app design process and explain why the described stages are crucial for the project’s success. I’ll also indicate some risks that will certainly occur while skipping particular phases so you will be aware of the consequences and ready to make informed decisions. You’ll also find some design tips for your app and check how the app design differs when web and mobile apps are concerned.

How to define “app design”?

App design focuses on a visual representation of the features and functionalities of an app. It combines user experience (UX) and user interface elements (UI). It would be best if you started with designing those each time you create apps.

User Experience is about functionality and utility. The more straightforward the usage of an app, the more attractive the app seems to be for users and the more willing they are to use it (and pay for it).

On the other hand, the User Interface is an app’s visual side, the app layout. It’s about colours, fonts and the general style of the app.

It’s not easy to design an app that is beautiful, trendy and won’t cause issues during usage. That’s why designers should always be a part of a project team to take care of the customers’ perspective.

Is it worth designing a mobile app’s User Experience and User Interface?

You probably wouldn’t entrust designing your house to a non-architect, which is also the case when digital products are concerned. Likewise, mobile and web apps should be created by specialists in order to address users’ needs and problems. Designers are one of them.

Around 25% of all mobile apps are abandoned after the first usage. That’s why taking care of the best user experience is extremely important (hand in hand with user interfaces). For every company losing users means losing money (from potential purchases, in-app sales or adverts). From this point of view, user experience defines your business’ success.

For users, a web or mobile app is a point of contact with your company. It’s part of your marketing and branding. Users’ experience while using your app defines how they perceive your company. The more they love your app, the more they love (and are loyal to) your brand.

We can say that app design defines the entire process of app development and its success or failure.

What to look for before you dive into the design process?

There are a few important aspects worth considering before starting app design. To make the mobile app a perfect match for your end users’ expectations, answer those questions:

  • Do you need a web app, a progressive web app or a mobile app?
  • On which platforms do you want to release the app? Should it be an iOS app, Android app or cross-platform app?
  • Who is an end-user of your app (define the target group)?
  • What makes clients more willing to use the app?
  • What business goals does your company associate with the app?
  • If you need both a mobile and a web app – are there different goals related to them?
  • How much money can you spend on the development (including app design)?
  • How’s the deadline? When should your app be launched?
  • What features or traits will make your app different from competitive ones?

Answers to these questions will define the direction of your project team and the app design.

Why are you going to design the mobile app?

App designers always start with “why?”. Answering this question is one of the essential aspects of the app design process as it defines the project’s goals.

Another benefit of specifying the goals is that it will help you stay on the right design patch. Getting lost in the maze of possibilities is easy, but written goals help you and your designers remain on track.

I advise you to ask yourself a bunch of questions listed below to find the meaning of the app:

  1. Who are the potential clients? How do they behave? What are their habits?
  2. What clients’ problems can we solve by providing them with the app?
  3. In what situations might they need to use your app?
  4. Why are those problems the most important ones?
  5. What makes your customers happy?
  6. What particular activities will users take in your app?
  7. How often will they use your app?

Answers to those questions will help you define what kind of app you need and prepare for the app design.

Is the research phase necessary?

Definitely yes! The next crucial step for a stunning mobile and web design is understanding the market and checking what your competitors do.

You should not ignore this stage as it might provide valuable insight into what people expect and in what direction competitive web or mobile apps are evolving. You can gather some app ideas and learn from their experience by reviewing simply a few apps made by competitive companies.

In this phase, you should conduct user research to reach real users and collect user feedback. You should ask your users directly what they really need and understand the environment and context in which the app will be used. You can use surveys, in-depth interviews or focus group methods to know how web or mobile users will interact with your app. You need to know that to build a perfectly-adjusted, successful app.

During your research, you should not forget to ask people what they think about other apps already available on the market. Ask them what is difficult for them when using those apps, what annoys them, why users abandon them, or what features/solutions are lacking.

You should already know the competitive solutions and understand their pros and cons. User research is the best opportunity to verify whether you and your users are on the same page and gain deep insight into their perspectives.

It would be best to establish what devices your target groups use to define screen sizes and resolutions you’ll focus on during the app design and development.

The research phase is also about establishing the budget for the app development and defining what target group is the best fit for your app. It would help if you also verified how much the target groups would be inclined to pay to use the app, as it gives you some insight into what level of Return on Investment (ROI) you can expect and in what period.

Hypothesis testing

When you collect answers to all the questions based on competition, market and user research, you’re ready to build a set of hypotheses. You need it to experiment, evaluate and validate your app idea.

It’s pretty simple: the quicker you validate the hypotheses (by testing), the sooner you discover whether you’re heading in the right direction.

There are many ways how to evaluate the app idea. You can, for example, conduct surveys and interviews based on paper prototypes and concepts. It’s priceless to see how people interact with a new product. Remember that the best way to succeed is by practice.

Omitting this step in the design process will affect the outcome. First of all, if you don’t test hypotheses, your final app might not be a perfect match for the target audience, and therefore, the ROI might be significantly lower (or the app might fail completely if you lose users).

Even if you decide to build an MVP and then change the project based on user feedback, you should be prepared for additional expenses. It’s definitely more costly to make changes to the project in the development stage or after the launch than during the conceptualisation/discovery phase.

You might be concerned about whether you really need to test the hypotheses; I know that. You might want to launch the app as soon as possible, and this stage might be considered a delay. In fact, you’ll spend some time understanding users, but you’ll save a lot of time and money during the following stages.

Requirements – what features should your mobile app have?

If you have your hypotheses tested, you should define what features and app functions the designed application should have.

Why should potential users use your web or mobile app? What can you offer them? How to attract them and convince them to use your app? What is a unique value proposition of your web or mobile app that differentiates it from the competitive ones?

At this stage, you should also define what kind of app you want to build (mobile app or web app), for what platform (iOS app, Android app or for multiple platforms), how (native or cross-platform/hybrid) and what technology you want to use.

That not only affects the features (and therefore design as you need to follow os design guidelines) but also narrows the pool of potential software development companies you should cooperate with.

To learn more about gathering requirements for your project, I suggest you check Gabriela Jarzębska’s article about software requirements specification. She’s our leading project manager and the best person to advise on this point.

Let’s talk about the details of our design

When you define the requirements and know what features your app should have, it’s time to build a roadmap that will be a base for the app design process.

Such a document contains all information about the project and helps all the teammates to be on the same page and up-to-date.

Remember, though, that the roadmap should not be rigid and created once in a lifetime. It should evolve based on user feedback.

It’s critical to understand that the most important is understanding end-users’ needs and the problems the app should be aimed at solving. It’s not enough to deliver a digital product because it is an art for the art itself. The more we know about problems and limitations, the better app we can build.

Such an approach is also helpful in communication between design and development teams. It helps everyone to comprehend each other properly and avoid misunderstandings.


Building wireframes is crucial for designing how users interact with the app. It’s a skeleton that reflects the core structure of the project (e.g. defines how many screens your app should have and how they should be interconnected). It helps to plan the content, the primary user interface elements and the user journey through your app.

Wireframes are a tool that connects the design and development teams and makes their cooperation more effective.

Wireframing is also another way to verify whether the project structure works. At this stage, all the stakeholders and the project team can test whether the solutions presented in wireframes are acceptable and understandable (e.g. the terminology is commonly understood and navigation straightforward).


Having wireframes, you can build a prototype. A prototype helps to understand how the final project should look like. It also provides insight into whether previous project decisions were appropriate (or maybe you should revise something).

A prototype is an application model that should be tested and constantly developed until all stakeholders agree it works as planned and accepts the final version.

Your prototype should be representative of what you want to achieve. You can use it to validate a particular task. It should be as straightforward as possible, with not too many visual elements that might disrupt and grab attention.

You will need a tool for prototyping that allows you to work efficiently and easily make changes to the project. It should also enable adding some interactive elements to the design. We use Figma in TeaCode.

UI design

If you have a prototype accepted by the stakeholders and the project team, it’s time to design the visual part of the app – the user interface (UI elements).

During this stage, your app designers will choose colours for your app, adjust the typography and plan an iconography to be understandable and visually attractive. The UI design phase is also when you decide about each element’s visual weight (e.g. user input and forms) and address different screen sizes.

Remember that many decisions at the UI design stage will define your branding (like colours, fonts or overall style).

You might need to develop a brand-new design system for your app according to your needs. A design system is a collection of reusable components (buttons, input fields, tables etc.) guided by clear standards. All the components can be assembled together to build any number of applications. Best known design systems are, for example, Material Design and Human Interface Guidelines.

During the UI design phase, you should also take care of micro-copy. That means you should write all the informative and persuasive micro texts for your web or mobile app designers and revise the navigation through the app. Whether you are about to build a web app or a mobile app is no different. You should provide users with a properly defined flow.

You should also define what UI elements you want to animate and how they should look.


When you know exactly how the app should look, you can start developing and implementing all the features.

As a designer, I don’t want to put a project manager’s shoes and describe how project management works and what developers do.

At this stage, my role in the project is not finished yet, even if developers are coding the app. There are many cases when developers need my assistance with design implementation (incredibly sophisticated ones).

From my experience, there are also many design adjustments at this stage, especially when the project is complex and long-term. In such cases, requirements constantly change, and so should the app design. When the project grows, additional screens should also be desired.


From the design perspective, it’s crucial to test the app properly. Quality Assurance engineers should test the app to verify whether it meets all requirements and expectations and behaves as planned. They should investigate whether there are no bugs or issues that might discourage people from using it.

What’s essential, testing should not be conducted by people involved in the project: developers, designers, project managers or stakeholders. Quality testing needs the fresh eye of someone who has never seen the app before (but knows the documentation and the app idea).

Quality Assurance engineers should test functionality, performance, security, bugs and issues, UI design and utility. You need to be sure the app looks like intended on all screen sizes and resolutions worth considering in your case.

The app is ready to be launched only when all issues are fixed.


When you have your app developed and it works as planned, it’s time for the launch. There’s no difference whether it’s a published website or mobile apps uploaded to Apple App Store or Google Play Store – it’s always a big deal for everyone (especially the designer 🙂 ).

That’s the moment when we’re sharing the fully functioning app with people and encouraging them to evaluate the app design and provide feedback.

There’s also a lot to be done after the launch. Having an app is like a continually evolving project – you should analyse people’s behaviour and respond to it by adjusting the app design and behaviour.

Best practices and app design tips

Based on my experience, I want to share some design tips with you.

  1. External consistency – ensure your app’s design is consistent with the website and other apps you own.
  2. Forms – designing contact forms ensures that the information needed for user input is minimal.
  3. Navigation – spaces and large buttons are especially important as mobile users shouldn’t be forced to click them precisely.
  4. Importance – put the visual weight on the most important elements like contact forms and CTAs. Guide people’s attention.
  5. Native features – gain advantage from native possibilities designing Android apps and iOS apps.
  6. Differentiate – change the elements’ design on mobile when needed. Not necessary solutions that suit desktops are appropriate for mobile app design (because of mobile screen size).

Web and mobile app design is always a teamwork

Designing an app for desktop or mobile devices is teamwork. Many people decide whether the project succeeds: project managers, project owners, UX and UI designers, content writers, developers and testers (to mention just the prominent roles of people engaged in the project!).

Although I described all those stages separately, keep in mind that the software development process is not that linear. In fact, many of those stages can interfere with each other or overlap and sometimes, there’s a necessity to take a step back. However, communication and understanding users’ needs are the key to a successful app.

The best fundament is trust. You’re not trusting companies but people with whom you will work. For this reason, I have one more hint: choose the development team, not a contractor. Choose people interested in your business and goals as you. That’s the best recipe for success.

She's a UX/UI designer driven by curiosity. She discovered her passion for experience design during her work in marketing. She likes observing people and finding out what engages them. Patrycja loves discovering user problems and addressing them with mindful design.

She constantly explores new ideas. That fuels me to provide TeaCode's clients with top-notch app design solutions that amaze end-users. She works hand in hand with marketers and developers to ensure end-users will be delighted with the app we're developing.

Patrycja Warzeszka
Patrycja Warzeszka

She's a UX/UI designer driven by curiosity. She discovered her passion for experience design during her work in marketing. She likes observing people and finding out what engages them. Patrycja loves discovering user problems and addressing them with mindful design. She constantly explores new ideas. That fuels me to provide TeaCode's clients with top-notch app design solutions that amaze end-users. She works hand in hand with marketers and developers to ensure end-users will be delighted with the app we're developing.