Design a mobile application with our agency now

By creating your mobile application with a trusted web development agency, in France, you control the design and functionalities, strengthening your online presence and engagement with your audience.

Interface application mobile Youcie
Interface application mobile Share With U
Interface application mobile Yure
Heinekein logoSimplon logoLVMH logoEiffage logoArt logoStellantis logoSNCF logoTBWA logo


Today, mobile applications are radically transforming the digital landscape. 40/60 Studio, a web agency specialized in innovation, is positioning itself as a key player in the creation and development of tailor-made mobile applications. Located in France in the heart of Paris, our agency excels in the development of mobile applications thus offering our customers powerful tools to optimize their performance and productivity.

The tailor-made expertise of 40/60 in mobile applications

We bring together a wide variety of experts, whether in design or web development. Thus, the studio excels in the creation and design of tailor-made, turnkey mobile applications that meet the specific needs of each project.

We are among the best agencies in Paris, in particular due to our experience and our ability to adapt to all types of projects.

Interface et compétences Yure

Technical skills at the service of your mobile application

Our broad expertise and technical know-how ensure quality results and a personalized user experience. Our development methods adapt to all environments, even the most demanding ones.

workshop d'équipe centré utilisateur

A personalized approach focused on user experience

Each mobile application we create is the result of close collaboration between target users, you, our designers and web developers, ensuring a perfect symbiosis between functionality and usability.

Atelier de réflexion

The assurance and reliability of our support

Our expertise is not limited to the visual aesthetics of mobile applications, it is dedicated to deploying ergonomic solutions tailored to each challenge. The objective? Digital products that not only captivate, but also make life easier for users.

Our mobile application offers for Start-ups and big companies

visuel représentatif offre startups

Our offers for start-ups

We understood very well that the launch of a mobile application is a key moment for a young start-up, which often leads to growth. Our services for start-ups include:

Define your mobile application

We work closely with you to define the ideal ergonomics of your product, ensuring that it perfectly meets user expectations.

Launch your mobile application

Our launch solutions are designed to ensure that your product makes a memorable first impression, with an intuitive and engaging customer user interface.

Boost your product to reach your product market fit

We help refine the ergonomics of your product so that it resonates perfectly with your target market, thus increasing your chances of achieving product market fit.

Understanding uses

We start with a thorough analysis of user behaviors and needs to ensure that our solutions are fully aligned.

Identifying opportunities

By identifying opportunities for improvement, we implement ergonomic strategies that maximize efficiency and commitment.

Realization of POC (Proof of Concept)

We develop prototypes to test and validate our ergonomic concepts, thus ensuring their effectiveness before full deployment.

Digital redesign

We offer redesign services to modernize and improve the ergonomics of your existing products, aligning them with the latest trends and technology.

visuel représentatif offre grandes entreprises

Our offer for large companies

In order to guarantee a personalized, so-called Taylor-made approach, we do not adopt a fixed process for large groups. Our aim is to ensure that all expectations are taken into account.

La Benefit that you need

The term of application is not associated with only a single service. Behind it lie multiple technical nuances, which are sometimes unknown. Our web development experts are here to help you determine the technology you need according to your specifications:

Native app

This solution is used on smartphones and tablets. It's good to know that it's developed for a specific operating system, whether it's iOS or Android. So this is the case with mobile applications.

Hybrid or cross-platform application

An option to consider when you want to develop a mobile application compatible with several platforms simultaneously (website, App Store, Google Play Store...).

Prestation atelier d'idéation
Prestation application youcie

These powerful tools are just a glimpse of the software integrated into our daily workflow, ensuring constant innovation for solutions tailored to the unique needs of our customers.

Our methodologies in application development agencies make it possible in particular to accelerate the launch of your mobile application, whether on iOS or Android.

Of integrated technologies in your mobile applications.

Mobile applications for a smartphone and a tablet are powerful instruments that can effectively captivate, convert and retain your customers. That is why the use of advanced technologies is necessary for creation and development of a mobile application. When they are precisely adapted to your application, they offer many advantages on both iOS and Android. Our experts choose the most appropriate technology during the production phase according to the challenges targeted.

Logo Flutter


This tool is an open-source framework that allows build mobile applications for Android and iOS with a single source code from Dart. It is appreciated by our studio's developer teams for its ability to provide mobile applications with a native look and feel without code duplication.

Logo Firebase


This platform for developing mobile and web applications was created thanks to Google and is still owned by Google. Firebase acts like an operating system. Its set of tools dedicated to hosting, file storage, the presence of a real-time database, and its range of complementary solutions allow developers to focus on creating functionality rather than managing infrastructure.

Logo Android Studio

Android Studio

As the name suggests, this official integrated development environment from Google has as main mission the development of Android mobile applications. Its advantage is the offer of a complete suite of tools for designing, coding, debugging, and deploying Android applications.

The approach proposed by our agency Mobile app

At 40/60, our methodological approach ensures the perfect balance between business goals and the needs of end users. Here's how:

User research and
clarification of needs

livrables recherche utilisateur web application

Objective: Gather user needs and/or business constraints in order to consider solutions in line with their expectations.

Method: We conduct interviews in the field to gather the needs of the target people. Our experts then analyze the results to draw lessons from them presented in a report, thus guiding further discussions.

Definition of uses and
selection of needs

Atelier d'idéation centré utilisateur

Objective: Refine thinking while maintaining a user-centered vision.

Method: Our web agency outlines the needs of your application or even before thinking about its design. Thus, we think with logical paths to better clarify the actions.

Interface design

Conception application mobile Yure

Objective: Land at clear, thoughtful and documented models.

Method: The employees of our agency work in two stages to design the interfaces. We start with a wireframe logic (low fidelity model, without graphic style) in order to test and validate the entirety of your mobile application. The interface of a mobile app has display limits compared to a web interface. Indeed, for mobile use, user action is more important than content compared to the small size of the screen and this is what is highlighted during design. Then, our design experts create UI models (high fidelity) that include all the graphical part of the interfaces.

Prototyping and user testing

prototypage et tests utilisateurs sur le terrain

Objective: Collect concrete data on user interactions on the mobile application.

Method: The teams proceed with the development of a real prototype in order to put the product into a real situation. Thus, we can collect concrete data that can then be used to make adjustments to the models in order to best correspond to business expectations/constraints.

Development & integration

développement et intégration web application

Objective: Make your mobile application real and technically usable.

Method: Our web design and development experts work in collaboration in order to achieve as much as possible what was decided during the user interface design phases. Our developers create all the models and set up a modern technical architecture in order to meet the requirements of the best mobile applications as much as possible.

A project in mind?
Let's work together!

Start a project
Personne autours d'une table qui participe à un atelier

The creation of a mobile application,
A challenge taken up with them.

Explore our rich portfolio of mobile applications for
assess the quality of our agency.


Development of an iOS and Carplay music application

1 project — An intuitive and engaging interface

Customer case: iOS and Carplay music application
Cas client Stellantis


Creation of an ecosystem of mobile applications that reinvents financial and administrative inclusion

1 project — Now operating on the market

Customer case: Yure applications
Cas client Yure

Discover all of our achievements

To conclude

In short, 40/60 Studio is more than just an innovation and creation agency - it is a partner committed to the success and innovation of your digital projects, counting among the best agencies in Paris. Our expertise in ergonomics, UX/UI design, and mobile application development, combined with our customer- and user-centered approach, ensures solutions that not only meet, but exceed, your expectations.

We invite you to connect with our experts to discuss your ideas and see how we can make your vision a reality. Visit our website to further explore our services, our achievements and discover how we can support you in the first creation of your mobile application.


A mobile application project? Let's talk about it!

Do you want to chat in person?
Photo de Quentin Da Silva
Quentin: 06 32 41 68 82
Quote de citation de témoignage
Photo de Marouane El Gueddah

Marouane El Gueddah

CEO of ADN Data

“By far the best agency collaboration”
Thanks for your message.
We will get back to you as soon as possible!
Oops! Something went wrong while submitting the form.