James Closs
Verified Expert in Engineering
Mobile App and Game Developer
Bath, United Kingdom
Toptal member since March 1, 2022
James is an award-winning digital media professional with 20+ years of experience specializing in cross-platform mobile app and game development and design using C#, Xamarin, and related technologies. James has developed apps on everything from the first Java-enabled mobile phones to contemporary game consoles and consulted at a senior level on major projects for high-profile clients, including Disney, Nokia, Cartoon Network, Open City, and Electronic Arts.
Portfolio
Experience
- Game Development - 20 years
- Mobile Game Design - 20 years
- Java - 20 years
- App Development - 10 years
- C# - 8 years
- Xamarin - 8 years
- C#.NET - 8 years
- Xamarin.Forms - 8 years
Availability
Preferred Environment
MacOS, Windows, Visual Studio .NET, Xamarin, Monogame, Xamarin.Forms
The most amazing...
...app development project I've completed was for the high-profile Open House London event, which attracted over 25,000 users during one weekend.
Work Experience
Creative and Technical Director
BitBull Ltd
- Developed cross-platform mobile applications for clients using Xamarin.Forms, including a Tamagotchi-style app to help children manage and track their screen time and a fitness tracker for a sports equipment manufacturer.
- Designed and developed Jetboard Joust, a retro-style arcade game, and ported it to all major desktop platforms and game consoles using C#, MonoGame, and associated technologies.
- Built 30+ mobile games for Java and Android phones, which were served on all major international operator portals, regularly featured in the ELSPA charts, and won several Pocket Gamer awards, including a Game of the Year nomination.
- Developed a Java-based middleware to enable J2ME/Java ME applications to run seamlessly in Java AWT desktop and Android environments with no code changes.
- Created an ANT-based build tool to enable 1,500+ mobile handsets of wildly varying specifications to be targeted from a single codebase and XML configuration file at the press of a button.
- Developed a Java framework for mobile and browser-based games. Aspects of the framework were licensed to Digital Bridges and Nokia for a six-figure sum.
- Built a browser-based dating application that included a multiuser live chat with virtual rooms and fully customizable avatars.
App Developer
Open City Architecture (Freelance)
- Developed the app to accompany the annual, high-profile Open House London event that attracted over 25,000 users in one mission-critical weekend.
- Collaborated with the back-end developer to specify the REST API that would give users access to comprehensive information on the approximately 1,000 participating buildings in a robust and efficient manner.
- Worked closely with the art director to ensure the integrity of the UI design across iOS and Android while maintaining a 98% shared codebase.
- Integrated Xamarin.Forms.GoogleMaps, an open-source, cross-platform solution for using Google Maps with Xamarin.Forms.
Creative Consultant
Fjord (Freelance)
- Worked on high-level conceptual design and storyboarding for a major new communities service for Orange (Hutchinson Telecom).
- Developed concepts for a series of augmented reality games for Nokia.
- Developed concepts and designed the UX for several mini-games for Nokia to promote its sponsorship of Disney's Tron Legacy movie.
Creative Director
SYZYGY AG
- Developed the creative concepts for numerous pitches, winning contracts from high-profile clients, such as Disney, Pepsi, Barclays, WPP, JWT.
- Developed the concept and oversaw the development of a browser-based, massively-multiplayer online game for Cartoon Network, probably the first of its kind using early web technologies.
- Concepted and oversaw the creative development of the first online eCommerce presence for Boots, the leading UK pharmacy-led health and beauty retailer.
- Developed the concept and oversaw the creative development of the first significant online presence for BP using early personalization technologies.
Experience
Open House London App
https://openhouselondon.open-city.org.uk/I was the sole developer of the app that accompanied the event and maintained it from 2017 to 2020, when the event was scaled back due to the COVID-19 pandemic. The app had regularly attracted 25,000+ unique users across the event weekend, and because of the time-sensitive nature of the project, it was absolutely critical that it ran without bugs.
I built the app in Xamarin.Forms with the vast majority of the codebase consistent across iOS and Android. I worked closely with the UI designer to maintain the integrity of the design across platforms and with the back-end developer to specify the REST API used to retrieve information on the participating buildings. Finding ways to asynchronously load large amounts of data without compromising the user experience was a key challenge.
Goozby | Screen Tracker App for Kids
The app required a native Xamarin component on each platform to maintain a background process that tracked the locking and unlocking of the user's screen. Users could challenge themselves not to exceed a certain amount of screen time per day and would receive feedback from their Goozby based on how they were performing.
Mobile Game Engine and Games
The framework included an emulation layer that enabled J2ME games to run in a Java AWT environment for desktop and browser and on Android phones with no code changes. It also included an ANT-based build tool that would target 1,000+ handsets with wildly different specifications from a single XML configuration file.
Education
Postgraduate Diploma in Graphic Design with Computing
Central Saint Martins School of Art - London, England, UK
Bachelor's Degree in Graphic Design
Central Saint Martins School of Art - London, England, UK
Skills
Tools
Visual Studio .NET
Languages
Java, C#.NET, C#, XAML, JavaScript
Frameworks
Monogame, .NET
Paradigms
UX Design, Mobile Game Design, App Development, UI Design
Platforms
MacOS, J2ME, Xamarin, Windows
Storage
JSON
Other
Xamarin.Forms, Interactive Media Design, Art Direction, Creative Direction, Concepting, Game Design, Game Development, Creative Concept Development, Games, API Integration, Graphic Design, Typography, Computer Graphics, Multimedia, Console Games, Multimedia Design, Web Technologies, Mobile Game Development
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