Senior Mobile App Developer, OnBuy

£55-60k

+ Equity

React

CSS

React Native

HTML

JavaScript

iOS

Android

Kotlin

Vue.js

Swift

Firebase

Flutter

Fastlane

Senior and Expert level

Remote from UK

Multi-category online marketplace

Be an early applicant

Multi-category online marketplace

101-200 employees

B2CB2BMarketplaceConsumer GoodseCommerce

Be an early applicant

£55-60k

+ Equity

React

CSS

React Native

HTML

JavaScript

iOS

Android

Kotlin

Vue.js

Swift

Firebase

Flutter

Fastlane

Senior and Expert level

Remote from UK

101-200 employees

B2CB2BMarketplaceConsumer GoodseCommerce

Company mission

To change online retail for the better, providing customers with a one-stop shopping destination that doesn’t compromise on value or values.

Job

Company

Role

Who you are

Proven experience developing and launching mobile apps for both iOS and Android
Frontend experience (with CSS, HTML and JavaScript. Vue.js — a big bonus)
Strong proficiency in Swift (iOS) and Kotlin
Experience working with Android Studio, Xcode, and Apple Developer Console
Solid understanding of the differences between iOS and Android ecosystems
Experience with Firebase, including FCM, App Distribution, and Realtime Database
Familiarity with CI/CD pipelines, automated testing, and deployment processes
Experience using tools like Fastlane to automate testing, building, signing, and publishing
Comfortable working in a start-up or scale-up environment with a fast-paced, agile approach
Excellent problem-solving skills and the ability to think algorithmically
Working knowledge of HTML, CSS, and JavaScript to support front-end development when required

Desirable

Full stack experience (including backend)
Experience with hybrid frameworks (e.g. React Native, Flutter) and integrating native functionality
Familiarity with analytics tools and performance monitoring for mobile apps
Contributions to open-source projects or a portfolio of published apps

What the job involves

OnBuy is on a mission to disrupt the eCommerce space with a fair, transparent, and seller-friendly marketplace. As we continue to scale, we’re investing in our mobile experience to better serve our customers and sellers. We're now looking for a talented Senior Mobile App Developer to join our growing tech team and lead the evolution of our mobile apps
Lead the development and maintenance of high-quality mobile applications from concept through to launch
Build robust, scalable, and performant apps for both iOS and Android platforms using Swift and Kotlin
Collaborate with backend and frontend teams to ensure seamless integration across the full stack
Implement and maintain WebView-based functionality while planning for a transition to more native app features
Integrate with Firebase services including Cloud Messaging, Realtime Database, and App Distribution
Manage app deployment pipelines using CI/CD tools like Fastlane and GitLab CI, including code signing and store submissions
Ensure secure coding practices and compliance with platform guidelines
Debug and resolve issues using platform-specific tools and logs
Implement features such as push notifications, deep linking, and gesture recognition
Support the wider development team with front-end tasks when needed, using HTML, CSS, and JavaScript
Contribute to architectural decisions and help shape the future of mobile at OnBuy

Our take

OnBuy claims to be the UK’s most trusted online multi-category marketplace, and the country’s most popular Amazon alternative. It’s a big claim, but it isn’t beyond reason. Along with Wish and Not On The High Street, OnBuy is certainly laying down a challenge to the likes of eBay, Etsy, and of course, Amazon.

The company differentiates itself from the competition in a few key ways – most of which are seller-related. Firstly, by not offering its own products, there’s no clash of interests with sellers (a common pain point for Amazon). As well as this, features like immediate payment and robust PayPal Seller Protection have aided its growth in popularity.

OnBuy’s sales skyrocketed during the first year of the pandemic, and the company has sustained its momentum since then; growing internationally, scoring major VC funding and expanding its executive team along the way. It has made a string of partnerships with companies such as Klarna and BaseLinker, all towards improving its services to ensure it maintains its position in the market.

Freddie

Company Specialist at Welcome to the Jungle

Insights

Top investors

-18% employee growth in 12 months

Glassdoor (2.9)

Trustpilot (4.4)

Company

Funding (last 2 of 3 rounds)

Jul 2021

$47.6m

SERIES A

Jul 2020

$6.8m

SERIES A

Total funding: $58.5m

Company benefits

Equity
Flexible Working Options

Company HQ

Westminster, London, UK

Leadership

Cas Paton

(CEO & Founder)

Before founding OnBuy they worked as a Retail and eCommerce Consultant, following a four year spell in the UK military.

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