Mobile games & audio books to teach sustainability for kids
Happy Little Planet App
ROLE: Digital product designer (ux/ui), graphic designer, project manager, design team lead, co-founder
TOOLS: Paper & pencil, Adobe Illustrator, Adobe Photoshop, Miro, Sketch, InVision, ChatGPT
DURATION: 4 years
Empowering kids to master sustainable living.
Imagine a world grappling with extreme climate catastrophes, huge wildfires and floods, food scarcity, extreme temperature shifts, increasing plastic pollution, and deepening social inequalities. Who wouldn't feel overwhelmed facing such a future? In 2020, two other mothers and I embarked on an ambitious mission: to help people—starting with our youngest generation—build a sustainable and hopeful tomorrow.
Instead of letting fear drive the narrative, we chose creativity and play as our tools for change. We breathed life into Lulu's world (The Happy Little Planet), a concept that resonated so strongly it won us the StartupHer competition in Hungary, launching us on an incredible journey.
The characters of the Happy Little Planet App
The Problem
As parents, we faced a challenging reality: preparing our children for a future vastly different from the world we grew up in. While we wanted to avoid instilling fear, we recognized the power of playful learning and positive thinking. Mobile games seemed like the perfect medium to begin this journey.
However, our search through app stores revealed a significant gap. Existing games either treated environmental issues superficially—focusing only on basic concepts like waste sorting—or ignored sustainability altogether. We found no applications taking a comprehensive approach to this crucial topic. Moreover, we were concerned that most games for kids were not just non-educational, but potentially harmful to young minds.
The Solution
We created Happy Little Planet: a thoughtfully designed collection of educational mobile games each paired with a corresponding audio book. This ecosystem guides children through the fundamental aspects of sustainable living in an engaging, age-appropriate way.
At the heart of our games and audio books is Lulu, the Little Planet, and her friends. Through single-player, open-ended role-playing games, children join Lulu's friends on their quest to help her feel better and become happy again.
This narrative framework makes complex sustainability concepts accessible and meaningful for young players.
To ensure comprehensive coverage of sustainability topics, we structured our content around the United Nations' 17 Sustainable Development Goals (SDGs), serving as a roadmap for young minds to explore and understand their role in creating a better future.
The very first video of the Happy Little Planet app.
The Process
Step 1 Discovery & research
Our journey began with comprehensive research across multiple domains to ensure we built something both meaningful and effective:
1. Understanding Sustainability Education We immersed ourselves in sustainability literature, consulted with environmental experts, and analysed how this crucial topic was being presented to children across various mediums—from books and educational platforms to workshops and school curricula.
2. Market Analysis We conducted an extensive review of children's apps, paying particular attention to game mechanics and success factors. This helped us understand what engages young users and why certain applications succeed while others may fall short.
3. User Research Our initial testing ground was perfect: our own children, aged 2-7, representing our target demographic. We observed their interactions with benchmark games and books, initiated conversations about sustainability, and carefully noted their responses and engagement levels.
4. Expert Consultation We expanded our research by interviewing early childhood development specialists, consulting kindergarten teachers, gathering feedback from other parents, engaging with sustainability experts.
The results were clear and encouraging: teaching children about sustainability through interactive, engaging methods wasn't just viable—it was necessary. Our market research and stakeholder interviews confirmed a significant gap in the market and a strong appetite for meaningful, educational content in this space.
Happy Little Planet
- The Games -
The Happy Moves game, aligning with SDG 3 (Good Health & Well-being), teaches children the connection between physical activity and mental well-being through playful movement. Children can follow along with the animals' exercises, create their own movement combinations, and control the music.
The game's impact extended beyond screen time—parents told us about their children spontaneously singing the melodies and recreating the dance moves in their rooms days after playing, showing how effectively the game encouraged healthy habits through play.
Wilson, Barnie & Mimi
The Happy Moves Game
- The Mini Games -
In Happy Little Planet, each character brings their unique profession to life (SDG 8 - Decent Work & Economic Growth). From Mimi the Gardener to Barnie the Doctor, Frankie the Civil Engineer, and Wilson the Trainer, our diverse cast introduces children to various career paths through playful exploration.
Through engaging dress-up and packing activities, children discover the tools and responsibilities of each profession, sparking early interest in different careers while learning about their importance in our community.
Step 2 Ideation
- Turning Global Goals into Child’s Play -
Our ideation phase was extensive, spanning multiple domains as we crafted not just games, but an entire brand around sustainability education. Before designing a single pixel or animation, we needed to lay a rock-solid foundation.
1. Understanding the SDGs We struck gold when Zsófi Tomaj joined our team—not just any sustainability expert, but the former UN team member who helped establish and write the 17 Sustainable Development Goals in New York. Having one of the "mothers of SDGs" on our team gave us unprecedented insight into these global objectives.
2. Building the Brand Armed with our research findings, we conducted intensive internal workshops to shape our brand and strategy. We defined clear objectives, identified our target audience, created detailed personas, mapped key stakeholders, and established project timelines.
Cards for identifying target audience personas
3. Making Global Goals Child-Friendly Perhaps our greatest challenge was translating the complex SDGs into engaging experiences for 3-7 year olds. Working closely with Zsófi, we tackled the monumental task of transforming these serious global goals into playful, age-appropriate games—all while maintaining their educational essence.
Through countless hours of brainstorming and creative iteration, we successfully broke down the SDGs into digestible concepts and daily habits that resonated with young minds. This intensive process yielded nearly 80 unique game concepts spanning all 17 SDGs.
With our ideas mapped out, we faced our next exciting challenge: transforming these concepts into delightful mobile experiences that children would love to play.
Our game ideas organised by SDGs
Step 3 Design
- Bringing Lulu's World to Life -
My design journey began with a personal foundation—a set of characters I had originally drawn to teach my daughter about animals and their sounds. While these illustrations provided the creative spark, they needed a complete transformation to work in a mobile game environment. I reimagined and modified them extensively to be screen-appropriate, and in the final stage, Fruzsi Gaál—my fantastic animation artist colleague and co-founder—helped polish them with minor tweaks to ensure smooth animation workflow.
Mimi, the fox girl
Frankie's truck from Time Machine
1. Game Format & Structure Our research guided us toward a single-player format combining life simulation and role-playing elements in an open-ended environment. To deepen the learning experience, we paired each game with an accompanying audio picture book—creating a rich, multi-layered educational experience.
2. Creative Process With around 80 rough game concepts developed during our ideation phase, we began by creating a priority list to determine our launch sequence. Once we established this roadmap and our design guidelines, our team dove into transformative brainstorming sessions for each selected game.
We prioritized humor throughout the design process, knowing that both research and experience show that learning sticks better when it's fun. While our creative ambitions sometimes soared beyond our budget constraints, this energy drove us to find innovative solutions within our means.
In Happy Little Planet, children explore different professions through dress-up mini-games, where each character brings their unique occupation to life.
3. Iterative Design Our process was deeply iterative, starting with my initial hand-drawn sketches that mapped out key game flows and interactions. I then evolved these rough concepts into polished digital designs using Sketch, carefully crafting each screen and element. One of the biggest challenges was designing for various mobile screen ratios—ensuring that every visual detail remained perfectly visible whether on tablets or smartphones, with no elements getting cut off at any screen size.
Throughout development, we conducted regular testing sessions with our target audience—including my then 3-year-old daughter, who became our most eager tester. Each design iteration was shaped by valuable feedback from children and their parents, and once the app launched in the stores, we continued to refine the experience based on user feedback and analytics.
Kids enjoyed the testing. They could really go nuts when they found a bug. :D
We redesigned the app's home page game selector to accommodate an unlimited number of games. While this change sparked intense debate among our team—and I had a particular attachment to our original 'signature' menu design—the need for scalability ultimately guided our decision. However, the analytics told an interesting story: purchase numbers seemed unaffected, and our young users actively missed the original rotatable earth menu they had grown to love. This became a valuable lesson in balancing scalability with user delight.
We redesigned the icon of the app too based on our app store analytics
and user-test results. The new icon brought us considerably more downloads.
4. Parallel Development While maintaining a tight schedule, we worked simultaneously on games and their companion audio books. As game designs moved to development, we shifted focus to book illustrations and audio production. Fruzsi masterfully handled animations, book illustrations and audio editing, while I took charge of preparing both the final screens in Sketch and all necessary files for developer hand-off.
Throughout the entire process, iteration remained our north star. Every element—from character animations to user interface controls—underwent rigorous testing and refinement based on real user feedback.
The Happy Little Planet App & Game Style Guide
Step 4 Development hand-off
- Bringing Designs to Life -
1. Comprehensive Documentation Every successful hand-off begins with meticulous documentation. I created detailed specifications that served as the development team's blueprint, including: screen-by-screen gameplay flows, interactive element specifications, character behaviour patterns, action-response relationships, while Fruzsi added animation timings, triggers, and sound effect mapping.
2. Collaborative Kick-off I led thorough walk-through sessions with our development team, establishing clear communication channels from the start. Regular check-ins helped us address challenges promptly and ensure the final product aligned perfectly with our vision.
3. Asset Management The technical hand-off process involved: uploading detailed screen designs and assets to Zeplin (a great software but sometimes required patience from me with large file transfers…), coordinating with Fruzsi to provide sound files and animation sequences, and ensuring developers had access to all necessary resources and information before coding began.
4. Iterative Development and Continuous Improvement While developers worked on one game, my team focused on creating the accompanying audio book for the next development cycle. This parallel workflow helped us maintain momentum while our launch wasn't the end—it was just another beginning as we conducted thorough testing before each release, monitored user feedback and analytics, quickly identified areas for improvement, returned to ideation and design when needed, implemented and tested refinements, released updates based on real-world usage.
This cyclical process of ideation, design, development, testing, and refinement continued throughout the entire project, helping us create increasingly engaging experiences with each iteration.
Reflection
- A Journey of Growth -
This project wasn't just work—it was a labor of love where every pixel and vector point mattered. From concept to completion, Happy Little Planet became more than a product; it was truly my digital baby, making the eventual letting go in the end both challenging and bittersweet.
Key Learnings:
As a Startup Founder: Clear role definition is crucial from day one—have everything in writing and stick to it. Without boundaries, you might find yourself spread too thin across unexpected responsibilities and that can be overwhelming. Entering the mobile game market, especially for children's apps, taught us hard but valuable lessons. While creating engaging educational content is crucial, it's only half the battle. Success in this space demands both a sophisticated market strategy and substantial financial resources to maintain visibility through app store optimization and sustained advertising campaigns. The path is challenging, but understanding these realities from the start is essential for any startup in this space.
As a Product Designer: thorough planning and preparation are the foundations of successful project management. Regular testing and iteration cycles are non-negotiable for product excellence. Dare to dream big first—let your imagination run wild before scaling back. Those "crazy" ideas often lead to the features that make your product truly unique. Trust your design instincts—when you deeply believe in a design decision, stand firm in your conviction.
Looking back, Happy Little Planet represents not just a collection of games and stories, but a testament to the power of believing in your vision. While the journey had its challenges, each obstacle contributed to both a stronger final product and a personal growth.
Check out more screens and videos of Happy Little Planet below!
In the Switch Off game through the guidance of Sigmund, children explore home and school environments to discover the importance of energy and water conservation (SDG 12 - Responsible Consumption & Production). From garage to rooftop, players embark on an engaging hunt to find and switch off unused resources.
Combined with its companion audio book, the game helps children understand not just how but why conservation matters, encouraging the development of sustainable daily habits that extend beyond gameplay.
Sigmund, Frankie & Ambie
The Switch Off Game
When playing with the Time Machine game kids join Frankie and his extraordinary time-traveling truck in a mission to clean up the streets (SDG 6 - Clean Water & Sanitation). Players sort through plastic, glass, organic, and aluminum waste while learning a crucial environmental lesson: how long different types of waste persist in our environment.
Through this unique blend of cleanup action and time travel, children discover the long-lasting impact of waste on our planet, making the abstract concept of decomposition times tangible and memorable.
Frankie & his future cleaning truck
The Time Machine Game
Alongside Mimi in the Plant a Tree game, children discover the vital role of trees and plants in our ecosystem (SDG 15 - Life on Land). Through planting seeds and saplings, players learn how these plants provide essential resources—from food through shelter to shade and clean air—for both humans and animals. The game transforms the simple act of planting into an adventure of discovery, helping children understand why every sapling matters for our planet's future.
Mimi & Sigmund
The Plant a Tree Game
Beyond the App: Visual Communication
- Brand Extensions & Marketing Materials -
While my primary focus was designing the characters, mobile games, and audio books, I also crafted the entire visual communication ecosystem for Happy Little Planet. This included creating: the logo, the website, digital advertisements, printed posters, promotional materials and brand communication assets. Here are a few selected examples of our visual storytelling.
This B1 size poster was designed for the Abu Dhabi WN 2024 Conference & Exhibition:
We took part in WN Gaming conferences as exhibitors in Istanbul and in Abu Dhabi.
Our badges from Istanbul 2022
Fruzsi & me at our tiny display in Abu Dhabi 2024
I also created Facebook ads, this canvas ad was designed for one of our campaigns that we ran in 2021:
In the Clean Hands game Ambie and his friends show how to master the art of proper hand hygiene (SDG 6 - Clean Water & Sanitation). Players learn not just how to wash their hands effectively, but why it's so important for our health. Using a magical magnifying glass, children can inspect their virtual hand-washing technique, making hygiene education both interactive and fun.
Magnus & Ambie
The Clean Hands Game
- From Audio Books to Animations -
The unexpected popularity of our audio books among young users inspired us to take storytelling a step further. We transformed these beloved stories into animatic films, bringing additional life and dimension to the original illustrations.
As head of design, I collaborated closely with Fruzsi and her animation team throughout this evolution. I participated in story development brainstorming sessions, helped refine narratives, and ensured all elements aligned with our brand guidelines. This evolution from static images to animated storytelling offered children another engaging way to explore sustainability concepts through the adventures of their favourite Happy Little Planet characters.
Have a glimpse into 'Lulu's Magic'
