How Belka built MangaYo! app in just 3 months with Expo

In August of 2023 MangaYo!, the biggest manga e-commerce business in Italy, asked Belka to help them build an e-commerce application where people can document their manga collection and buy mangas. In November that application shipped and hit 10,000 downloads on its first day.

It took only three months to build and ship this performant, resilient application to the masses. Let’s take a look at how the Belka team used Expo to speed up their development process.

But first…

Belka is a digital product studio based in the heart of the Italian Alps. They help expand the products of European tech companies to accelerate their growth.

They use systemic thinking when it comes to products, so design systems are their tool of choice when it comes to scaling and growing high-quality products both on the web and mobile.

They already worked with companies such as Scalapay — one of Europe’s unicorns, Fatture in Cloud — Italy’s fastest-growing SaaS company and indigo.ai, a hyper-growth conversational AI startup.

In order to build and ship the MangaYo! app in three months Belka tapped three developers: Fabrizio Rizzonelli, Anas Araid and Federica Vacca.

• Fabrizio cut his teeth in Android Development and was not impressed with React Native when he first dipped a toe in 2017. But today he admits that React Native is the only logical solution when you need to build an app to consume APIs and show data to users.
• Anas was a React web developer who evolved into a React Native developer. Just as nature intended.
• Similar to Anas, Federica started her career in web development and then moved to mobile with React Native (which she now prefers). Her focus is on frontend development.

The app was released on November 1st, the same day as LuccaComics - the largest comics festival in Europe, and the second biggest in the world after the Comiket. MangaYo! quickly grew from zero to 24,000 users:

It’s easiest to think of the app as the Manga version of IMDB. People create their own profiles where they keep track of Mangas they’ve read and Mangas they want to read. So it’s essentially an inventory management application. But the app is also a place where individuals can search for a Manga they want and buy it from MangaYo!. So there was a big e-commerce component to figure out.

“Without Expo we could never have built this app in three months.” - Anas

MangaYo! was responsible for prototyping the application screens in Figma and then they passed those screens to Belka. At the same time Belka started building out the backend of the app. They chose to use Supabase to handle the infrastructure APIs.

“Supabase and Expo appear to have a similar philosophy. We liked the way they fit together.” - Fabrizio

Belka has worked with Expo in the past and they chose it again for this project because it speeds up development by removing the need to work on native code or to ever touch Xcode or Android Studio.

The other fundamental benefit of building with Expo is the strength of the documentation and the general Expo ecosystem. For example, Anas needed to implement Apple and Google sign-in. Without Expo this would have been a substantial step in the development cycle. But with Expo he just followed the documentation, configured the plugin, and got it done in one sprint.

Prior to this project for MangaYo!, neither Anas or Fabrizio had ever experienced the magic of EAS Build. They had always just run builds and their machines and waited for them to complete, and then managed fastlane, and provisioned fios…ect. It was a lot of manual labor.

With EAS Build they just run a command and everything else is automated. They also used EAS Submit and a lot of different Expo plugins like Sentry and Apple. But Fabrizio says the best part of Expo is how simple it is to get through the gauntlet of Apple credential requirements. Expo automates the process of signing up your app for Apple (and Android).

The combination of EAS Build, Submit, the plugins, and all the automation of painful little boilerplate development tasks allowed Fabrizio, Federica, and Anas to stay focused on building out the features and shipping an app in three months.

The app is steadily growing in popularity, adding an average of 400 new users every day. Soon there will be a need to try out EAS Update for shipping over-the air-updates directly to their users. Federica and Anas are also working on: enabling Instagram-like stories and notifying users once their new favorite mangas get released. All the new features aim to make this the definitive app for tracking manga collections.