01
Mobile Applications
I build native and cross-platform mobile applications with a focus on clear interfaces, useful features and an experience that feels intentional rather than generic.
About me
Hello, I'm Jeronimo Junior.
I'm an independent developer from Brazil and the creator behind JJ Studio Entertainment. I enjoy turning ideas into working products — from practical mobile apps to games and interactive experiences.
My journey
Technology has changed. The curiosity stayed the same.
My path in software development has taken me through very different technologies and ways of building software. I started learning programming with languages such as COBOL and later expanded into C and C++, mobile development, game engines and modern cross-platform tools.
Today, my work spans Swift and SwiftUI for Apple platforms, Flutter for cross-platform applications, and Unity and Unreal Engine for games and interactive projects. I like understanding how a product works from the inside while also paying close attention to how it feels to the person using it.
JJ Studio Entertainment is where these interests come together. It is the home for the apps, games and experiments I build and publish, while the main JJ Studio website focuses on technology articles, tutorials and practical guides.
What I build
Different platforms. One product mindset.
02
Games
Games let me combine programming, interaction and visual design. My portfolio includes mobile titles as well as smaller browser-playable projects and experiments.
03
Interactive Projects
I also enjoy smaller technical experiments where I can test ideas, mechanics and interfaces before deciding whether they should grow into larger products.
Toolkit
Tools change. Strong fundamentals remain useful.
I don't define my work by a single framework. I choose tools according to the product and keep learning as platforms evolve.
That flexibility has allowed me to work across mobile apps, games and web experiences without treating every project as the same problem.
Apple Development
Cross-platform
Game Development
Programming
Platforms
How I think about products
Build it clearly. Make it useful. Keep improving it.
Interfaces should explain themselves.
I prefer experiences that are easy to understand without making the user fight the interface.
Details matter after the feature works.
Functionality comes first, but spacing, typography, motion and feedback are what make a product feel complete.
Every project should teach me something.
I like leaving each project with a better understanding of the platform, workflow or technology I bring into the next one.
Continue exploring
The best way to understand my work is to see what I've built.
Explore the apps and games in my portfolio, try one of the browser games, or get in touch if you'd like to talk about a project or opportunity.