iOS Architecture Patterns Explained: Know Which One Suits Your Project

Do you know an average American checks their mobile phone over 344 times a day? It means every four minutes, they will take a look at their device. What do you think is the reason for this immense dependency? What made smartphones a constant companion of people?

Well, it’s the magic of mobile applications. Every time the screen glows with your favorite mobile app notification, you will probably glance at it. This unseen popularity and ever-growing addiction to mobile applications have skyrocketed the growth of the mobile app industry, especially in the realm of iOS.

However, developing an app could be challenging, especially when you have no idea which iOS architecture pattern to follow. Without a suitable architecture pattern, laying a foundation for your app could become a tough row to hoe.

It’s crucial to consider your project’s requirements before picking up an iOS architecture pattern. This informational piece will talk about the most prominent ones out there and how choosing the right one can significantly enhance your app’s performance.

iOS Architecture Patterns: An Overview

How do you describe a mobile application as good or bad? You might consider its loading speed, interface, or ability to navigate the features. In a nutshell, you might say that it’s the app’s performance and accessibility that make it stand out in the market. However, achieving it isn’t that easy. In order to make your app user-friendly and smooth, picking a suitable architecture pattern plays a significant role.

An iOS app architecture pattern provides the developer with a set of techniques that help them build a well-structured mobile application. It’s like a base, the initial building block on which the entire app architecture is developed.

Choosing the best iOS architecture pattern for your project can help prevent unstructured programming and code duplication. It further develops a good and healthy coding environment for the developers. 

Why Are iOS Architecture Patterns Important for Your App?

When there is less coding involved, the chances of errors in it fall, too. An iOS architecture pattern avoids code cluttering and helps developers write concise code. Here are some of the advantages of having a good app architecture pattern:

1. Prevent unscripted documentation and unorganized code modules
2. Create precise and compatible code structure
3. Equally distributes responsibilities among various entities
4. Easy testing at separate development stages
5. Reduce coupling between different components and classes
6. Enhance ease of accessibility
7. Low maintenance cost

What Are the Most Prominent iOS Architecture Patterns to Look for?

Model-View-Controller (MVC)

There is a reason why MVC appears first in this list, and that is its popularity. As a widely used mobile app architecture recommended by Apple, it is equally popular in both the app and web development spheres.

MVC architecture separates the presentation layer from the business logic, dividing the program logic into three elements:

1. Model- This element acts as a database responsible for managing and storing data.
2. View- It helps represent data in different graphical forms, such as tables, charts, diagrams, etc.
3. Controller- This element works as a mediator between the model and the view. In the MVC architecture, it is often regarded as the brain of the application.

Features and Advantages of MVC Architecture

1. One of the most popular iOS app architecture patterns used in both app and web development
2. Easily separates the responsibilities between the server and the client
3. MVC can act as a good option for planning development
4. Promotes code reusability and extensibility
5. Code maintenance and modifications become easy in this architectural pattern.
6. You can test all three elements separately.

Model-View-Presenter (MVP)

Often seen as an inference to the MVC architecture, MVP is widely used for developing creative UIs. The major difference between MVC and MVP is that the Presenter in the latter replaces the Controller in the former. However, the link between the presenter and the other layers brings additional work, reducing the development speed. The three significant elements in the MVP architecture are

1. Model- This layer is responsible for storing data and deploying UI elements.
2. View- This is the graphical user interface (GUI) layer, where data is displayed graphically in the form of charts, tables, and diagrams.
3. Presenter- This element forms a bridge between the model and the view layer. Unlike MVC, the MVP architecture moves much of the view logic into the presenter.

Features and Advantages of MVP Architecture

1. Performing unit testing is less tedious. 
2. Verification of the correct functioning of each component becomes more accessible in MVP
3. Including the Presenter promotes a deep understanding of the view and the model layer.
4. Explicitly separates responsibilities among different components.

Model-View-ViewModel (MVVM)

Developers often make their way toward the MVVM architecture whenever there is a need to separate too much logic handled by the View controller. This logic is moved into a separate component known as the ViewModel. The primary role of this component is to make the view controller more manageable and load-free. The three sections in this app architecture pattern are

1. Model- Like in other iOS architecture patterns, the Model is responsible for holding data.
2. View- This layer shows the formatted data to the users through the GUI.
3. ViewModel- The data is retrieved from the Model and exposed to the View in this layer. This is where you place and read all the variables from the View controller to update the user interface.

Besides this, there are also four principles associated with the MVVM architecture:

1. The Simplicity Principle- For each View, there will be only a single ViewModel. Moreover, each ViewModel can only service a single View.
2. The Blendability Principle- The ViewModel must provide Expression Blend support.
3. The Designability Principle- The ViewModel must offer the Design Time data.
4. The Testability Principle- Testability must be possible in both the Model and the ViewModel.

Features and Advantages of MVVM architecture

1. It could be the Best iOS architecture pattern if your project consists of simple business logic and has less complex use cases
2. Tweaking and extending the code is much easier.
3. The inclusion of ViewModel makes handling logic seamless
4. Smooth and transparent communication along the Model and the View layer
5. Ensures quick and easy testing of the components

Model-View-Controller-ViewState (MVCVS)

The MVCVS architecture is somehow a combination of MVC and MVVM architecture. It follows MVC to expand; however, it relates to MVVM when it comes to patterns. The view controller in this app architecture determines the modifications in the model layer, unlike the view model in MVVM. Moreover, in order to make it more efficient, the view state is separated, making the overall process more manageable. Here are the phases involved in this architecture:

1. MVCVS Initialization- In this stage, the view controller has to follow both the model and the view state.
2. MVCVS Model Updates- If any modifications occur, the view controller updates the document model and view state.
3. MVCVS View Changes- The view state analyzes the document view model and the view state. It further makes changes to the view according to the observations.
4. MVCVS View State- The view controller and the view state are separated. It takes charge of updating the view state and listens to the changes whatsoever.
5. MVCVS Testability- In this app architecture pattern, testing is done through integration tests. You can test the logic of the view and document models separately, making it more efficient than MVC.

Features and Advantages of MVCVS Architecture

1. A highly manageable and efficient application architecture pattern
2. Quick and easy testing of separate components with the help of integration tests

VIPER

VIPER (View, Interactor, Presenter, Entity, and Routing) is one of those iOS architecture patterns known for the clean structure of iOS applications. It is a perfect choice when you need to create components around specific use cases.

Even though it is highly efficient, it is also one of the most challenging patterns to start with, as it requires different components to work. Due to the massive requirement of the same code, the developers who work on the VIPER architecture usually use code generators. The various components included in VIPER are:

1. View- Whenever the presenter conveys the view, the latter displays it. Based on the user interactions, the view reverts to the presenter with messages.
2. Interactor- It is primarily responsible for carrying the business logic.
3. Presenter- This layer consists of the view state and its logic. It controls and changes the view based on the actions performed by the interactor.
4. Entity- These are the basic models used by the interactor.
5. Routing- The router is responsible for managing the views, like which view will be shown or what view should be displayed next.

Features and Advantages of VIPER Architecture

1. Simplifies the most complex projects
2. An easily manageable architecture pattern for large development teams
3. Promotes code reusability
4. Creates well-defined and interactive UIs
5. Dissociates code for quick and seamless testing
6. Mitigates the number of merge conflicts

The ELM Architecture (TEA)

TEA is new to the realm of iOS architecture patterns and quite different from the rest of the model-x design structures. In this, the view state and the model are single entities. All updates regarding these components are shared as messages to this single combined element and are managed through methods known as reducers.

The way events flow in this iOS app architecture design is unidirectional. It’s somehow similar to Facebook’s Flux or Redux if you have an idea about it.

Features and Advantages of the ELM Architecture

1. One can describe the views in this architectural pattern as pure functions.
2. One-way binding from the model layer to the view component

Coordinator Patterns

Well, to be frank, it is not exactly an architectural pattern but a design pattern that resolves most of the issues other coupled architectures, such as MVC or MVVM, couldn’t fix. Basically, it creates and handles a reference to the scene’s view controller. With the help of this instance, it can present a new screen or push a new view controller to its navigation controller.

Features and Advantages of Coordinator Patterns

1. It easily separates the navigation logic from the rest of the scene. 
2. Creates a transition between two screens

Critical Factors to Consider While Choosing an iOS Architecture

As mentioned in the beginning, the first and foremost aspect to look for while choosing an iOS app architecture design is your project’s specific requirements. However, here are a few significant factors that you can consider while making your decision.

Figure out the issues with the code

Before proceeding with an iOS architecture pattern, it is crucial to identify and understand the existing state of your codebase. You can evaluate and choose the suitable architecture pattern for your app based on the observations.

Enhances UI and strengthens the code quality

One of the primary objectives of an app architecture design is to rectify the issues in the UI and make it highly engaging. Therefore, when working on object-oriented programming, pick an architectural pattern whose model can manage and improve the components’ interactivity.

The complexity of the application

Each app project has unique design objectives, and only some specific tools or architectural design patterns can fulfill those. Hence, you must describe what UI design and features you want in your app so that the development team can understand its complexities and choose the best iOS architecture pattern for your application.

How Can Appventurez Help You Choose the Right iOS Architecture for Your Project?

If you have made it to this point, you probably have an idea about all the popular iOS app architecture patterns out there. This article has also provided a brief about the relevance of iOS architecture patterns and how they can enhance your app’s performance.

So, have you made your choice yet? Or do you still need to decide which one to pick from this list? When all the options seem interesting, no doubt it becomes challenging to make a decision. But you don’t have to worry; you can always consult a professional iOS application development services to help you choose the best option for your project. The development team at Appventurez consists of highly experienced and proficient developers who are always ready to turn your dream app project into a reality!