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  1. Stackups
  2. Application & Data
  3. Frameworks
  4. Cross Platform Mobile Development
  5. Expo vs J2ObjC

Expo vs J2ObjC

OverviewDecisionsComparisonAlternatives

Overview

J2ObjC
J2ObjC
Stacks8
Followers20
Votes6
GitHub Stars6.0K
Forks991
Expo
Expo
Stacks811
Followers693
Votes66

Expo vs J2ObjC: What are the differences?

Developers describe Expo as "Making React Native Easier". Exponent lets web developers build truly native apps that work across both iOS and Android by writing them once in just JavaScript. On the other hand, J2ObjC is detailed as "Java to iOS Objective-C translation tool and runtime used by Google Inbox to share 70% of its code across Android, iOS, and Web". J2ObjC is an open-source command-line tool from Google that translates Java code to Objective-C for the iOS (iPhone/iPad) platform. This tool enables Java code to be part of an iOS application's build, as no editing of the generated files is necessary. The goal is to write an app's non-UI code (such as data access, or application logic) in Java, which is then shared by web apps (using GWT), Android apps, and iOS apps.

Expo and J2ObjC belong to "Cross-Platform Mobile Development" category of the tech stack.

"Free" is the primary reason why developers consider Expo over the competitors, whereas "Backed by Google" was stated as the key factor in picking J2ObjC.

Expo and J2ObjC are both open source tools. It seems that Expo with 6.78K GitHub stars and 791 forks on GitHub has more adoption than J2ObjC with 5.47K GitHub stars and 771 GitHub forks.

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Advice on J2ObjC, Expo

John
John

Feb 11, 2021

Decided

Our stack roughly divides into three major components, the front-end, back-end and the data storage.

For the front-end, we have decided to go with React Native via Expo. This allows us to target both Android and iOS with a single codebase. Expo provides "managed workflows" and an SDK that will simplify development and deployment.

For the back-end, we have decided to use Python. Python is the language of choice for machine learning (ML). It has extensive support for traditional ML algorithms (e.g. random forests) via Scikit-Learn and the SciPy ecosystem. On top of this, our industry partner has provided us their current solution written in Python. We decided to expose the back-end as a REST API using FastAPI. This allows us to nicely separate concerns from the rest of the codebase. FastAPIs use of static type hints, validation with Pydantic, and automated documentation allows us to build better APIs faster.

For data storage we decided to use a MongoDB Atlas, a NoSQL database. We decided to use a NoSQL database because we need to store large amounts of data (e.g data from the wearable IMUs). Moreover, due to the ever changing nature of a startup we require flexibility. NoSQL databases are schema-free which enables us to modify our schema as we see fit.

We plan on using GitHub Actions (GA) to orchestrate our CI/CD. Given GAs broad support of languages and workflows, it's hard to go wrong with this decision. We will also be using GitHub for version control and project management, so having everything in one place is convenient.

The major components of our CI/CD for the backend will consist of black for autoformatting, flake8 for linting, pytest for unit-testing, and mypy for static type checking and codecov for coverage reporting. We plan to use separate Docker containers to package the back-end and front-end components and use Docker Compose to launch the app. This allows us to better separate concerns, manage dependencies, and ensure our app is deployable anywhere.

109k views109k
Comments
Furqan
Furqan

Jul 16, 2020

Needs adviceonReact NativeReact Native

Hello guys, I am new here. So, if I posted without specific guidelines, please ignore.

Basically, I am an iOS developer and developing native apps for the last three years. Recently, I started learning React Native to develop apps for both platforms. If anyone out there knows any useful resources that will become a better react native developer.

@{#newbie}|topic:null|

325k views325k
Comments

Detailed Comparison

J2ObjC
J2ObjC
Expo
Expo

J2ObjC is an open-source command-line tool from Google that translates Java code to Objective-C for the iOS (iPhone/iPad) platform. This tool enables Java code to be part of an iOS application's build, as no editing of the generated files is necessary. The goal is to write an app's non-UI code (such as data access, or application logic) in Java, which is then shared by web apps (using GWT), Android apps, and iOS apps.

It is a framework and a platform for universal React applications. It is a set of tools and services built around React Native and native platforms that help you develop, build, deploy, and quickly iterate on iOS, Android, and web apps.

Statistics
GitHub Stars
6.0K
GitHub Stars
-
GitHub Forks
991
GitHub Forks
-
Stacks
8
Stacks
811
Followers
20
Followers
693
Votes
6
Votes
66
Pros & Cons
Pros
  • 4
    Backed by Google
  • 1
    Access to existing Java libraries
  • 1
    Made it possible to quickly port a hardware driver
Pros
  • 15
    Free
  • 13
    Hot Reload
  • 9
    Common ios and android app setup
  • 9
    Easy to learn
  • 6
    Streamlined
Integrations
Java
Java
Objective-C
Objective-C
React Native
React Native

What are some alternatives to J2ObjC, Expo?

Ionic

Ionic

Free and open source, Ionic offers a library of mobile and desktop-optimized HTML, CSS and JS components for building highly interactive apps. Use with Angular, React, Vue, or plain JavaScript.

Flutter

Flutter

Flutter is a mobile app SDK to help developers and designers build modern mobile apps for iOS and Android.

React Native

React Native

React Native enables you to build world-class application experiences on native platforms using a consistent developer experience based on JavaScript and React. The focus of React Native is on developer efficiency across all the platforms you care about - learn once, write anywhere. Facebook uses React Native in multiple production apps and will continue investing in React Native.

Xamarin

Xamarin

Xamarin’s Mono-based products enable .NET developers to use their existing code, libraries and tools (including Visual Studio*), as well as skills in .NET and the C# programming language, to create mobile applications for the industry’s most widely-used mobile devices, including Android-based smartphones and tablets, iPhone, iPad and iPod Touch.

NativeScript

NativeScript

NativeScript enables developers to build native apps for iOS, Android and Windows Universal while sharing the application code across the platforms. When building the application UI, developers use our libraries, which abstract the differences between the native platforms.

Apache Cordova

Apache Cordova

Apache Cordova is a set of device APIs that allow a mobile app developer to access native device function such as the camera or accelerometer from JavaScript. Combined with a UI framework such as jQuery Mobile or Dojo Mobile or Sencha Touch, this allows a smartphone app to be developed with just HTML, CSS, and JavaScript.

Framework7

Framework7

It is a free and open source mobile HTML framework to develop hybrid mobile apps or web apps with iOS native look and feel. All you need to make it work is a simple HTML layout and attached framework's CSS and JS files.

Qt

Qt

Qt, a leading cross-platform application and UI framework. With Qt, you can develop applications once and deploy to leading desktop, embedded & mobile targets.

PhoneGap

PhoneGap

PhoneGap is a web platform that exposes native mobile device apis and data to JavaScript. PhoneGap is a distribution of Apache Cordova. PhoneGap allows you to use standard web technologies such as HTML5, CSS3, and JavaScript for cross-platform development, avoiding each mobile platforms' native development language. Applications execute within wrappers targeted to each platform, and rely on standards-compliant API bindings to access each device's sensors, data, and network status.

Vue Native

Vue Native

Vue Native is a mobile framework to build truly native mobile app using Vue.js. Its is designed to connect React Native and Vue.js. Vue Native is a wrapper around React Native APIs, which allows you to use Vue.js and compose rich mobile User Interface.

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