In this article, we want to share with you our experience of using and adapting the architecture of the Viper by describing our own example of development. And today we're going to discuss the basics&hellip; &nbsp;
Many developers face an issue when code becomes hard to read, debug and fix bugs. Classes become huge together with adding features and development turns to infinite &ldquo;bugfixing&rdquo;. That&rsquo;s why it&rsquo;s important to choose proper software architecture before developing an application, otherwise, it will consume much time to maintain and improve. As a result, it will help to save time and efforts, so proper architecture is the first step to success!
<h2 style="text-align: justify;">Perfect architecture</h2>
Quality architecture should meet the following requirements:
<ol dir="ltr">
<li style="text-align: justify;">The effectiveness of performing the assigned tasks. If designed architecture performs the tasks poorly and doesn't fit into the requirements of functionality, stability, performance, and development time, it can hardly be called a good one.</li>
<li style="text-align: justify;">Well readable and understandable code. First and foremost, a code should be clear and properly structured.</li>
<li style="text-align: justify;">The scalability and flexibility of the system. A good architecture allows you to painlessly add new entities and functions, as well as make changes to existing functionality.</li>
</ol>
However, there is no reason to reinvent the wheel and spend a lot of time developing a completely unique architectural pattern. It's much easier to use the existing one.
There&rsquo;re several most famous architectures named MVC, MVP, MVVM, VIPER. Let&rsquo;s probe deep into each of them.
<h2 dir="ltr" style="text-align: justify;">MVC (Model View Controller)</h2>
MVC is the most simple architecture Apple recommends.
<img style="border: none; width: 512px; height: 208px;" src="https://d12zh9bqbty5wp.cloudfront.net/images/f9e66e179b6747ae54108f82f8ade8b3c25d76fd30afde6c395822c530196169-1676631376053.png" alt="^56BDEBB44AF88BAB8B39A1A9F8FC649A23FC487FB5D45024D5^pimgpsh_fullsize_distr.png" />
The basic idea of MVC architecture is to split up all the elements (fragments) of the code into three separate units: the Model (domain data or a data access layer), the View (user interface) and the Controller (interface between Model and View). MVC allows each block to be controlled independently of the two others, and it greatly simplifies and systematizes the development process.
MVC implies that the Model manipulates data and provides it to the Controller that renders the View. And the View remains stateless just displaying data of the Model to a user.
However, the described model may not work perfectly in all conditions. And in reality, the View and the Controller often become a single unit looking like this:
<img style="border: none; width: 512px; height: 61px;" src="https://d12zh9bqbty5wp.cloudfront.net/images/f9e66e179b6747ae54108f82f8ade8b3c25d76fd30afde6c395822c530196169-1676631386327.png" alt="2.png" />
So, ViewController transforms into the Massive View Controller forced to handle almost all the processes itself. And the main task for developers, in this case, is to offload it.
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<h2 dir="ltr" style="text-align: justify;">MVP (Model View Presenter)</h2>
It turned out that in some cases MVC architecture is not working as effectively as one expects (for the reasons described above). So there was MVP pattern designed, having become a bit improved version of MVC. 
The difference between MVC and MVP is the Presenter acting as the mediator between the View (actually ViewController) and the Model. The Presenter significantly unloads the ViewController by moving business logic to the Presenter, so the ViewController is only responsible for the layout and its lifecycle.
<img style="border: none; width: 512px; height: 199px;" src="https://d12zh9bqbty5wp.cloudfront.net/images/f9e66e179b6747ae54108f82f8ade8b3c25d76fd30afde6c395822c530196169-1676631396862.png" alt="" />
This architecture makes it easier to mock the View, the Presenter and the Model that leads to better testability of the code which is an obvious advantage of MVP.
<h2 dir="ltr" style="text-align: justify;">MVVM (Model View ViewModel) </h2>
Another popular pattern is MVVM (Model View ViewModel). It looks similar to MVP architecture, but instead Presenter it has ViewModel between the View (view controller) and the Model (data).
<img style="border: none; width: 512px; height: 43px;" src="https://d12zh9bqbty5wp.cloudfront.net/images/f9e66e179b6747ae54108f82f8ade8b3c25d76fd30afde6c395822c530196169-1676631408723.png" alt="3r.png" />
The important difference of this model from the MVP is that ViewModel doesn&rsquo;t refer to View, it works directly with model updating it with user interactions from View and receives updates from Model updating only itself (not View). View can receive updates using observer if needed. So ViewModel prepares the data for View that unloads controller.
<div>
<h2 dir="ltr" style="text-align: justify;">VIPER</h2>
The last architecture we will talk about is VIPER. It&rsquo;s a very effective architecture pattern, in fact, the first one that cares about navigation (routing) between modules.
It consists of 5 parts: View, Presenter, Interactor, Entity, Router.
<ul dir="ltr">
<li style="text-align: justify;">The view is the ViewController. The View&rsquo;s waiting for the Presenter to transmit the content and display it to a user; it never requests the data from the Presenter.</li>
<li style="text-align: justify;">Presenter prepares data for the View. It gathers data from user interactions and can send requests to the Interactor. The Presenter also gets results from the Interactor and convert the results to a state being most effective to display on the View.</li>
<li style="text-align: justify;">Interactor (a new unit) contains the business logic and networking for managing objects (Entity) to perform a specific task.</li>
<li style="text-align: justify;">Entity is the objects managed by the Interactor. So it&rsquo;s actually a model.</li>
<li style="text-align: justify;">Router (another new unit) is responsible for segues between modules.</li>
<li style="text-align: justify;">Data Store (e.g., web service, database) provides the Entity to the Interactor. Applying its business logic, Interactor selects the Entity from the data store, manages it and then returns it in an updated form back to the datastore.</li>
</ul>
<img style="border: none; width: 512px; height: 196px;" src="https://d12zh9bqbty5wp.cloudfront.net/images/f9e66e179b6747ae54108f82f8ade8b3c25d76fd30afde6c395822c530196169-1676631418693.png" alt="4.png" />
VIPER module is a user story that can be represented either as one screen or as a whole story. The good example is a registration flow consisting of several screens such as SignUp, Confirmation, etc.
Each module being an independent part requires an additional unit able to manage the entire process. This role is played by the Configurator which task is not only to create a module but also provide it with all necessary Services and information.
<h2 dir="ltr" style="text-align: justify;">Improving and Simplifying VIPER at the same time</h2>
VIPER architecture was reliable and usable from the outset, but <a href="https://github.com/strongself/The-Book-of-VIPER" target="_blank" rel="nofollow noopener">Rambler Digital Solutions</a> has improved and simplified it even more. Let&rsquo;s take a look at the main changes:
<ol dir="ltr">
<li style="text-align: justify;">Assembly functions which Wireframe was responsible for are moved to Configurator now. So, after this modification, Wireframe is in charge of Routing and nothing else.</li>
<li style="text-align: justify;">The router has become global</li>
<li style="text-align: justify;">All data transfer is executed according to ModuleInput and ModuleOutput protocols</li>
<li style="text-align: justify;">View is not only ViewController now; it acts as a presentation layer containing several parts (View, DataSource&rsquo;s. Delegate&rsquo;s, etc.)</li>
<li style="text-align: justify;">A new service layer has been added to a module with dependency injection into interactor. Thanks to this improvement a module interacts just with required services (they make networking, storing, collecting, etc.).</li>
</ol>
Thus, the VIPER is quite a useful architectural system, allowing to distinguish all of the logic, so that every class performs only actions it is responsible for.
<img style="border: none; width: 512px; height: 240px;" src="https://d12zh9bqbty5wp.cloudfront.net/images/f9e66e179b6747ae54108f82f8ade8b3c25d76fd30afde6c395822c530196169-1676631429726.png" alt="6.png" />
This is the first part of our article about using and adapting the Viper architecture. In the <a href="https://agilie.com/blog/the-use-and-adaptation-of-the-viper-architecture-on-our-own-example-of-development-part-2" target="_blank" rel="nofollow noopener">second part</a>, we're going to discuss structuring and creating project skeleton for VIPER.
Follow our blog to learn more about the architecture of VIPER!
</div>
</div>

In this article, we want to share with you our experience of using and adapting the architecture of the Viper.&nbsp;&nbsp;

General info about software architectures

The use and adaptation of the VIPER architecture on our own example of development, part 1

In our <a href="https://agilie.com/blog/what-type-of-restaurant-app-is-best-for-your-business">previous article</a> devoted to restaurant app development, we highlighted two types of restaurant apps on the market: 1) restaurant discovery and booking platforms, and 2) branded standalone restaurant apps. We wrote about some successful products out there and made our points in favor of both types of apps.
Now, we&rsquo;re going to outline all major benefits mobile apps for restaurant owners can provide. There are lots of them, so we decided to accumulate these benefits into the seven most important things that will help you enhance your services as you decided to go mobile.
<h2 style="text-align: justify;">1. Fast and easy customer experience</h2>
A mobile app helps restaurant owners establish a fast and convenient customer experience, which means reduced wait time and increased sales.
Table booking is the first feature that comes to mind when you&rsquo;re thinking about a restaurant app. However, as we stated in the earlier article, it&rsquo;s not the best strategy to focus on table reservations only. First, they don&rsquo;t guarantee any ROI for restaurant owners. Second, for big and crowded restaurants or chains online bookings, if not organized right, can lead to a real logistical hell at the restaurant. In a case when a restaurant often has free tables, booking feature is simply unnecessary.
Meal ordering is a more valuable feature, that, unfortunately, is less utilized by restaurant app developers. However, allowing app users to choose and order their meals in advance, thus significantly reducing visitor&rsquo;s wait time, will help not only establish better customer experience at your restaurant but also make the staff&rsquo;s work easier and faster.
You can add even more value to this feature by letting app users browse their order history and store their favorite orders. This will make the ordering process even faster and convenient.
<img style="width: 800px; height: 464px;" src="https://d12zh9bqbty5wp.cloudfront.net/ckeditor_assets/pictures/220/content_panera_roll.jpg" alt="Panera food ordering app" />
<a href="https://www.panerabread.com/en-us/home.html">Panera Bread</a> - one of the most popular apps focused on meal ordering functionality
<h2 style="text-align: justify;">2. Expand your target audience with active mobile users</h2>
As the <a href="https://www.adweek.com/performance-marketing/survey-25-of-users-have-at-least-one-restaurant-app-on-their-phone/" target="_blank" rel="noopener">latest surveys suggest</a>, people - especially those between the ages of 25 and 34 - tend to use mobile apps to discover restaurants and make reservations. Furthermore, 25% of respondents have at least one restaurant app installed on their device.
Catching up with this trend will not only make restaurant&rsquo;s services better for the existing customer base but also appeal to young people who seek for a good restaurant mobile service. Finally, to retain this audience you&rsquo;ll need to ensure three things: the app, the restaurant services, and the food.
<h2 style="text-align: justify;">3. Better discovery</h2>
And by discovery, we mean all possible ways a mobile app can make a restaurant more visible to the customers. <a href="https://agilie.com/expertise/technology/mobile-development">Mobile technologies</a> help deliver the information on a restaurant location, menu and establish an emotional connection with customers by memorable restaurant app design.
The most obvious thing here is discovering a restaurant's location with the help of mapping services. This feature is a must for restaurant and food discovery apps like OpenTable and Urbanspoon, as well as for large chains&rsquo; branded apps.
But people need to know not only the restaurant&rsquo;s location. They also need to know what does the restaurant have to offer. A mobile app solves this by providing customers with easy menu access. The menu is more appealing when the meals are illustrated with appealing photos. Just note that the reality must correspond to what people see in the app and vice versa.
In the same fashion, restaurant owners can show off their places providing alluring interior photos or even 3D tours to the restaurants.
Nice photos aside, a thoughtful restaurant <a href="https://agilie.com/expertise/technology/ui-ux-design">app design</a> helps establish a visual communication between restaurant owners and customers, make both an app and a restaurant distinctive and build brand awareness.
Adding social sharing features can help extend the brand awareness to users&rsquo; friends and followers on social networks like Facebook, Twitter, and Instagram. You can reinforce this feature rewarding users with loyalty points for each share. (We&rsquo;ll touch upon loyalty programs later in the article).
<img style="width: 800px; height: 486px;" src="https://d12zh9bqbty5wp.cloudfront.net/ckeditor_assets/pictures/221/content_coast_roll.jpg" alt="coast restaurant app" />
Agilie&rsquo;s <a href="online-food-ordering-systems-how-to-create-a-restaurant-online-ordering-website">Coast</a> restaurant app was among the first on the local market to provide social sharing and 3D-tour features
<h2 style="text-align: justify;">4. Retain users more effectively</h2>
Mobile apps' landscape knows a variety of successful approaches to retaining users. &nbsp;Among such features that restaurant mobile app developers can adopt are loyalty programs and user notifications.
Loyalty programs. Both table booking services and restaurant apps retain their users mostly thanks to loyalty programs with discounts and rewards. Gift cards and coupons are things customers tend to lose so stubbornly, and mobile loyalty programs are the best solution to this problem so far.
In our previous article, we mentioned the case of Starbucks&rsquo; app which, thanks to gamification elements and transparent reward system, got a significant rise in user base right after the introduction of the new loyalty program.
<img style="width: 800px; height: 480px;" src="https://d12zh9bqbty5wp.cloudfront.net/ckeditor_assets/pictures/222/content_starbucks_roll.jpg" alt="Starbucks reward system" />
<a href="https://www.starbucks.com/">Starbucks</a> Coffee Company&rsquo;s app owes its latest success to a new reward program
Notifications. Regardless you want to build your own restaurant app or to provide discovery and booking services, you can keep your app&rsquo;s users informed about the latest deals using email and push notifications. If the deals are regular and fair, and the notifications are personalized, people will anticipate them and, thus, appreciate notifications as a useful service rather than as annoying spam.
<h2 style="text-align: justify;">5. Delivery</h2>
Today, extending a restaurant service with the food delivery feature becomes a reasonable option for restaurant mobile app developers. And while it may not be the primary feature to include in a new app, it&rsquo;s still a prospective direction for restaurant services.
Moreover, there are restaurants that serve their customers only with food delivery using mobile apps and websites for ordering. One of the most successful among the delivery-only restaurants is Ando, a part of a large US-based restaurant chain <a href="https://momofuku.com/">Momofuku</a>.
<img style="width: 800px; height: 479px;" src="https://d12zh9bqbty5wp.cloudfront.net/ckeditor_assets/pictures/223/content_ando_roll.jpg" alt="ando food delivery app" />
Momofuku&rsquo;s Ando - a delivery-only restaurant operating via an iOS app and a website
<h2 style="text-align: justify;">6. More payment options</h2>
Online payments are a big thing now. All types of digital solutions dealing with commerce have adopted it, so have restaurant apps.&nbsp;
There are two types of online payments you can adopt as a restaurant app developer to make restaurant services more effective. The first is mobile payments processed via payment gateways such as Stripe or Braintree (a PayPal subsidiary).
However, restaurant owners may dislike this idea if mobile payments service is provided by a booking platform since it would mean more additional fees that may have a negative impact on the ROI.
<h2 style="text-align: justify;">7. Sufficient feedback</h2>
The last for this article but not the least important thing for a business&rsquo;s success is gathering visitor&rsquo;s feedback. Most of the restaurant apps and food discovery platforms provide users with the possibility to leave a review on their restaurant visit.
User reviews play two important roles at the same time. First, as a business owner or/and service provider, you can get feedback on your services to understand how to improve them, thus satisfying your customers even more. But - not less importantly - your visitors&rsquo; reviews act as additional motivators for other people to visit a certain restaurant. Thus, it may be a logical decision to place user reviews on the apps/restaurant&rsquo;s website and allow people to share their reviews.
Want more insights on <a href="online-food-ordering-systems-how-to-create-a-restaurant-online-ordering-website" target="_blank" rel="noopener">restaurant app development</a> for your business? <a href="https://agilie.com/contacts">Contact us</a>, and we&rsquo;ll be happy to discuss it with you!

Let's explore how a restaurant&nbsp;can acquire more customers and provide better services adopting mobile technologies.

Let's explore how a restaurant can acquire more customers and provide better services adopting mobile technologies.

7 Most Important Things Mobile Apps Can Provide to Restaurant Businesses

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