How to Design the Architecture of a Mobile Application

Creating a successful mobile application requires careful planning. The architecture of an app is its foundation, determining its structure, component interactions, and ultimately its performance and scalability. In this article, you will learn the key aspects of architecture design that will help you create a reliable and efficient mobile application.

What is Application Architecture

Application architecture is like a skeleton or framework on which all software is built. It defines the structure of the application, the relationships between its components, and the principles by which it operates. Simply put, it is a plan that describes how all parts of the application will interact with each other to achieve a common goal. The architecture of a mobile application plays an important role and performs the following functions:

  • Improves code understandability. A good architecture makes code more readable and understandable, simplifying maintenance and development.
  • Increases scalability. A well-designed architecture makes it easy to add new features and scale the application to meet growing workloads.
  • Simplifies testing. An architecture that divides the application into independent components streamlines the testing process.
  • Reduces development time. Reusable components and a clear structure accelerate the development process.

The architecture of an application includes several major components. The user interface is the primary element with which the user interacts. The application logic performs the main tasks, processes data, and is responsible for decision-making. Data refers to the information the program works with (e.g., user data or application settings). The database is a crucial component responsible for storing the data used by the application.

Mobile Application Architecture Requirements

A properly chosen application architecture enables the extension of functionality without significant code revisions. Additionally, it allows most changes and bug fixes to be implemented easily, ensuring high application performance. The main principles of mobile application architecture include the following:

  • Separation of Responsibilities. Each component of the application should have clearly defined tasks.
  • Modularity. Breaking an application into independent modules.
  • Encapsulation. Hiding the internal implementation of components and providing only a public interface.
  • Abstraction. Creating abstract representations of data and operations to increase flexibility.
  • Testability. Simplifying the process of writing tests to verify the correctness of component operation.
  • Performance. Ensuring the application architecture provides high performance.

Other requirements for the application structure include clarity and simplicity. Moreover, the architecture should be flexible, enabling easy modification and the addition of new functionality. The main architectural patterns used in mobile app development are as follows:

  • MVC (Model-View-Controller). A classic pattern that divides an application into a model (data), a view (interface), and a controller (logic).
  • MVVM (Model-View-ViewModel). An extension of MVC, where the ViewModel acts as an intermediary between the View and Model, providing a closer connection between the interface and data.
  • MVP (Model-View-Presenter). Similar to MVC, but the Presenter has full control over the View and interacts with the Model.
  • Clean Architecture. An architectural style that focuses on separation of concerns and ensures the independence of internal components from external frameworks.
  • BLoC (Business Logic Component). A pattern based on data flows where the application state is updated through events.

When selecting a pattern, the complexity of the development should be considered. For initial projects, it is recommended to choose simpler solutions that are easier to implement in practice. The choice of a pattern should also facilitate writing tests and scaling the program code. There are various types of mobile application architecture, each characterized by its unique features and attributes.

SOLID Mobile Application Architecture SOLID is a set of object-oriented programming principles that help create more flexible, scalable, and easily maintainable systems. When applied to mobile applications, SOLID enables the development of modular, independent components that simplify both development and testing. The main features of this type of application architecture include the following:

  • S – Single Responsibility Principle Each class should have only one reason to change.
  • O – Open-Closed Principle Classes should be open for extension but closed for modification.
  • L – Liskov Substitution Principle Objects of a base class must be replaceable with objects of derived classes without altering the correctness of the program.
  • I – Interface Segregation Principle Clients should not depend on methods they do not use.
  • D – Dependency Inversion Principle Dependencies should rely on abstractions rather than specific classes.

This is a universal principle of mobile application programming that ensures the timely modernization, updating, and extension of functionality as needed.

KISS Mobile Application Architecture KISS (Keep It Simple, Stupid) is a design principle that advocates for systems to be as simple as possible. In the context of mobile application development, this principle emphasizes that the application architecture should be understandable, easily maintainable, and extensible. The main reasons for choosing this type of architecture include the following:

  • Improved code readability. Simple code is easier to understand and maintain, which shortens development time and reduces the likelihood of errors.
  • Accelerated development. The simpler the architecture, the faster new features can be implemented.
  • Increased reliability. Fewer complex components mean fewer potential points of failure.
  • Improved scalability. A simple architecture is easier to adapt to growing requirements.

By adhering to the KISS principle, you can create applications that are easy to develop, maintain, and scale. This principle encourages minimal coding and the use of a simple technical stack.

DRY Mobile Application Architecture DRY (Don't Repeat Yourself) is a fundamental principle of software development that states every piece of information should have a single, authoritative representation within the system. In the context of mobile applications, this means that code, logic, and data should not be duplicated. Developing an application architecture with the DRY principle:

  • Improves maintainability. When changes are needed, you only have to update the code in one place instead of searching and fixing it in multiple duplicates.
  • Reduces the number of errors. Less code means fewer opportunities for errors to occur.
  • Increases readability. The code becomes more concise and easier to understand.
  • Simplifies testing. Fewer repeated code sections mean fewer tests are required.

f a block of code is used in multiple places, it should be placed in a separate function or method. Values that are used in several locations should be stored in variables or constants. Frequently used data sets or functionalities can be encapsulated in separate classes. Design patterns provide ready-made solutions to common problems, helping you avoid "reinventing the wheel." For example, let's examine a DRY application architecture in JavaScript. Suppose in our JavaScript application we need to display a date in a specific format several times. Instead of writing formatting code repeatedly, we can create a function:

By applying the DRY principle, you can significantly optimize the code, making it better and more efficient.

How to Build an Application Architecture

Building an application architecture is the process of creating a foundation for your software product. A good Android application structure ensures the longevity, scalability, and maintainability of the application. Well-structured code is easier to understand and maintain. Additionally, a well-designed structure facilitates the addition of new functions and modifications to existing ones. Many components can also be reused, which speeds up the development process and simplifies code navigation. The process of creating an application architecture is as follows:

  1. Requirements Analysis. At this stage, functional and non-functional requirements for the application are thoroughly studied. Different categories of users and their needs are identified.
  2. Selection of Architectural Style. The architecture is chosen based on the specific project's context. It is important to consider project requirements, team size, and the technology stack.
  3. Component Design. The application is divided into logically related modules, and the interactions between them are defined. Appropriate technologies are selected for each module. UML diagrams (classes, components, sequences) are used to visualize the architecture.
  4. Implementation. At this stage, components are developed in accordance with the project architecture. All components are then integrated into a single system.
  5. Testing. Individual modules are tested to ensure their correct functionality and seamless interaction. Testing is performed at every stage of development to achieve optimal results.
  6. Deployment and Maintenance. The application is deployed on the chosen platform. This is followed by performance monitoring and bug fixing.

The overall structure of an application is dynamic. It evolves and adapts with the project. Regular reviews and updates to the architecture will ensure the application remains relevant and efficient.

Create the Overall Application Logic

Creating the overall application logic is one of the key stages of application architecture development. It determines how the application will function at the algorithmic and data levels. This forms the foundation of the application, defining its behavior and functionality. Several steps are required to accomplish this:

  1. Analysis. At this stage, the primary functions of the program are clearly defined. The main entities with which the application will interact (e.g., users, products, orders) are identified. The actions that can be performed with these entities are determined.
  2. Data Structure Design. A data structure is chosen to store various types of information. Efforts are made to eliminate data redundancy and inconsistency, while relationships between different entities are established.
  3. Algorithm Development. For creating the structure of a typical mobile application, the most efficient algorithms are selected to perform the required tasks.
  4. Implementation in the Selected Programming Language. A programming language is chosen, and the code is then developed and tested accordingly.

For example, let's consider the structure of a simple shopping cart application. The user can add or delete items, view the list of items, and calculate the total value of the cart:

Creating the application architecture is the basis for further development. The quality of this work determines the reliability, performance and usability of the entire application.

Building the Right Application Interfaces

Creating an effective user interface (UI) is an important step in developing a typical application architecture. A good UI is not only visually appealing but also intuitive and easy to use. The basic principles of creating proper application interfaces include:

  • Simplicity. The simpler the interface, the easier it is to use. Avoid unnecessary information and complex hierarchies.
  • Intuitiveness. The interface should be so clear that users can understand how to use it without needing instructions.
  • Consistency. All interface elements should maintain a uniform style, layout, and behavior.
  • Feedback. Users should always understand the outcome of their actions.
  • Accessibility. The interface should be usable by all users, including those with disabilities.

Consider examples of application architectures with effective interfaces that truly work. For instance, the Calm meditation app employs simple shapes, soft colors, and minimal elements to create a soothing atmosphere. Google Maps allows for intuitive navigation using zoom and scroll gestures. Social media apps display notifications for new posts and likes, providing users with instant feedback. Among the main patterns for designing application structures are the following:

  • Cards. Used to present individual items of information (e.g., news or products).
  • Hamburger Menu. Hides navigation options behind an icon featuring three horizontal lines.
  • Modal Windows. Used to display additional information or collect input from users.
  • Tabs. Allow users to switch between different sections of the application.

Various tools are available for creating interfaces, with popular options including Figma and Adobe XD. Designing the right application structure is an iterative process that involves continuous testing and refinement.

Add logic for each application format

Adding logic to an application involves creating rules and actions that define how the application responds to user input and processes data. The logic varies depending on the type of application and its functionality. When designing logic, it is important to consider key aspects such as:

  • Understanding the subject area: A deep understanding of what the application does allows for the creation of more efficient logic.
  • Choosing the right algorithms and data structures: The performance and scalability of the application depend on these choices.
  • Error handling: Different error scenarios must be anticipated, and the application must respond appropriately.
  • Security: When handling user data, security measures must be implemented to prevent hacking.

For native applications, platform-specific programming languages and tools are used to implement the native application architecture. For hybrid applications, web development languages like HTML, CSS, and JavaScript are used in conjunction with frameworks such as React Native or Flutter to create the user interface and access native features. Some of the major components of a mobile application include:

  • User Interface (UI): Defines the appearance and user interaction with the application.
  • Business Logic: Implements the core functions of the application related to its tasks.
  • Data: Storage and processing of data received from the user or external sources.
  • Network: Interaction with a server to exchange data.
  • Notifications: Sending notifications to the user.

Let's consider examples of developing the logic of the system architecture of an application system for mobile devices (in JavaScript):

Once you have written a module with a common logic and structure, you can no longer refer to this code, but use it to add various new formats and data structures.

Summary

The architecture of a mobile application is the foundation upon which the entire project is built. It defines the structure, interaction of components, and principles of application operation. A properly chosen architecture ensures the long-term success of the project, allowing for easy scalability, maintenance, and development of the application. Developing the structure of a mobile application requires a high level of professionalism from developers, so it is recommended to seek the help of professionals.