Web Developer

Sensor Tower

Location: London, United Kingdom
Job Type: full-time
Salary: Unknown
Posted: August 10, 2025

Job Description

About this role:

Sensor Tower is the leading provider of market intelligence and insights for the mobile app ecosystem. Our data-driven solutions empower businesses, developers, and marketers to make informed decisions and stay ahead in the competitive mobile landscape.

We are looking for a skilled Front-end Developer to join our team and enhance our web presence, optimize user experience, and support our marketing and product initiatives. This role will involve building and maintaining high-performance, visually engaging, and user-friendly websites that drive engagement and business growth.

What You Will Focus On:

Lead the development of our Sensor Tower’s marketing website, taking ownership of the project’s direction, and quality.
Continuously improve the marketing website's architecture, ensuring scalability, maintainability, and performance.
Implement new features, landing pages, and updates to improve user experience and support business goals.
Optimize website performance, SEO, and conversion rates using best practices.
Ensure website security, accessibility, and compliance with industry standards.
Integrate third-party tools, APIs, and analytics for enhanced functionality.
Work on front-end initiatives for Sensor Tower’s product.
Conduct testing and debugging to identify and resolve technical issues.
Collaborate with marketing, design, and engineering teams to define priorities, gather requirements, and ensure seamless integration of UI/UX elements.
Stay up to date with the latest web development trends and technologies to continuously improve the website.

Skills We Are Interested In:

Proficiency in HTML, CSS, JavaScript, TypeScript and modern front-end frameworks (React, etc).
Nice to have: Experience with technologies such as MUI, Next.js, GraphQL, Highcharts, and Marketo. While not required, familiarity with any of these will be an advantage.
Experience with headless CMS platforms (Contentful, Strapi, Webflow, or custom-built CMS).
Strong knowledge of SEO best practices, web analytics, and performance optimization.
Understanding of web security principles and best practices.
Strong problem-solving skills, attention to detail, and ability to work independently.
Excellent communication and collaboration skills.

If you’re passionate about front-end development and want to make an impact at a fast-growing technology company, we’d love to hear from you!

About Sensor Tower

Sensor Tower cultivates responsibly sourced market intelligence that provides visibility into the trends shaping the global digital economy. Our customers use these insights to help them make better business decisions.

Why Sensor Tower?

Our flexible work environment allows employees to live in greater connection with the people, places, and activities they love!

Our benefits for full-time positions include:

- Flexible time off so employees can shape their time away from work.

- Health and wellness stipend to achieve and maintain a healthy lifestyle through physical and mental fitness.

- Monthly internet stipend and a one-time $500 home office stipend.

We are committed to equal employment opportunity regardless of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital status, disability, gender identity, and veteran status. We will consider qualified applicants with arrest and conviction records. If you have a disability or special need, please do not hesitate to let us know and we'll do our best to accommodate.

🎯 Who is this job for?

This role suits a Middle to Senior Front-End Developer with strong skills in HTML, CSS, JavaScript/TypeScript, and React, plus experience with performance optimization and SEO best practices. Ideal candidates are familiar with headless CMS, API integrations, and tools like Next.js, GraphQL, or MUI. You should be comfortable leading website development, improving architecture, and collaborating with cross-functional teams to deliver engaging, high-performance web experiences.

💬 Potential Interview Questions

What are the key differences between HTML5 semantic elements and non-semantic elements?
Semantic elements convey meaning about their content (e.g., <header>, <article>), improving accessibility and SEO, whereas non-semantic elements like <div> and <span> provide no inherent meaning.
How would you optimize a React application for better performance?
Techniques include code splitting with dynamic imports, memoization (React.memo, useMemo), avoiding unnecessary re-renders, and lazy loading components.
What are the benefits of using TypeScript in a front-end project?
TypeScript provides static type checking, improved developer tooling (autocompletion, refactoring), and helps prevent runtime errors.
Can you explain how Next.js improves SEO compared to a standard React app?
Next.js supports server-side rendering (SSR) and static site generation (SSG), which provide fully rendered HTML to search engines, improving crawlability and ranking.
How would you implement accessibility best practices in a marketing website?
Use semantic HTML, proper ARIA attributes, keyboard navigability, and ensure color contrast meets WCAG guidelines.
What is a headless CMS and how would you integrate one like Contentful with a front-end?
A headless CMS stores and delivers content via APIs, allowing developers to fetch content with REST or GraphQL and render it in a front-end framework like React or Next.js.
How do you ensure web security in front-end applications?
Implement HTTPS, sanitize user inputs, use Content Security Policy (CSP), and avoid exposing sensitive data in the client code.
What are some best practices for SEO optimization in modern web development?
Optimize page load speed, use descriptive meta tags, structure content with headings, and ensure mobile responsiveness.
How would you integrate third-party analytics tools into a website?
Embed tracking scripts or SDKs as per the provider’s documentation, often in <head> or via a tag manager, ensuring GDPR and privacy compliance.
What steps would you take to debug a front-end performance issue?
Use browser DevTools to analyze network requests, identify slow scripts, profile JavaScript execution, and check for layout shifts or memory leaks.

📋 Job Summary

Join Sensor Tower, the market leader in mobile app intelligence, as a Front-End Web Developer to craft high-performance, engaging websites that drive business growth. You’ll lead the development of our marketing site, build new features with HTML, CSS, JavaScript, TypeScript, and React, and work with tools like Next.js, GraphQL, and Contentful. This is a full-time, remote role offering flexible time off, wellness and internet stipends, and a \$500 home office setup allowance. Be part of a collaborative team shaping the future of the mobile economy while enjoying the freedom to work from anywhere.