JOIN App
JOIN Global SAS, 2024 – Present
Overview
A small French startup set out to challenge the current financial system. I joined the tech and marketing team as a founding designer, responsible for both product design and brand identity. Our goal was to create a mobile app for crypto enthusiasts that would simplify crypto while serving as a robust, self-custodial digital asset management tool.
We focused on eliminating the common barriers that often intimidate newcomers: seed phrases, gas fee management, complex bridging, time-consuming on/off-ramps, and cluttered layouts.
Understanding the task
The vision for the final product shifted over time and continues to evolve today. My core responsibility was to design from scratch a fully functional app with all essential features, while ensuring it remained flexible enough for future updates.
I also had to be conscious of our limited resources, which meant building a comprehensive design system that reused components wherever possible rather than multiplying instances. As a cherry on the top, we needed to develop a distinctive visual identity.
PRD I built in Notion to stay in touch with the stakeholders
Research
Initial research included analyzing major crypto platforms and innovative startups, along with traditional banking apps and financial services like Wise and Revolut.
While many design patterns followed traditional banking apps, crypto-specific concepts needed clear communication. One of the key finding was the importance of displaying asset networks throughout the whole user flow, despite potential interface clutter.
We also build user personas together with the marketing team to increase empathy and target them more effectively.
User personas in FigJam
User flow
I like the object-oriented user interface (OOUI) approach to wrap my head around a complex app. And I think it works best when combined with the user’s mental model rather than being purely based on technical structure.
Crypto and traditional currencies are different by nature but represent parts of the user’s portfolio. If so, as a user, I want to simply swap any crypto from any network and transform it to fiat and back.
So I took an asset as a key object. All assets share similar traits: price, value, profit'n'loss, and they can be bought, sold, or exchanged. That helped me define key screens and flows that can be adapted across scenarios with minimal changes.
User flow in FigJam
Wireframing
To avoid misunderstanding and missed scenarios, I first create wireframes to get early feedback. This also helps to identify the main components for the future design system.
Some initial wireframes
Mockups and branding
Time to bring in the brand identity and give the app the right look’n’feel.
The logo concept: two pills — blue for traditional finance, magenta for crypto. Their intersection forms a deep navy.
The UI color scheme extends this metaphor — from deep navy to pale lilac, with pink as an accent. Lilac in varying opacity helps distinguish component states in both light and dark modes. The matte-glass illustration style adds a futuristic, techy feel while representing transparency.
JOIN App home screen in dark and light themes
Design system
I start building design system with primitive tokens (numeric values and color codes) and then define semantic tokens based on them:
#032A65
navi-600
#F9FAFB
neutral-50
--color-ui_element-variant-state
When designing components for the design system, I follow atomic design principles — reusing elements whenever possible instead of multiplying instances.
Some components from the design system
Prototyping and testing
Never miss prototyping — both at Lo-Fi and Hi-Fi stages. Some flares can be easily missed on static screens but become obvious when you interact with them.
From the very beginning, we were fortunate to build a community of crypto enthusiasts. Their ongoing engagement helped us understand user needs, test the prototypes, and gather valuable feedback.
Prototype for usability test
Launch and outcome
1000+
active users in a month
We launched the JOIN App on both iOS and Android. And we hit over 1,000 active users within the first month after the launch.
Reviews have been positive, with users praising the smooth UX and pleasant UI. People especially liked the fast on/off-ramp and seamless cross-chain conversions. Kudos to the developers who nailed all the complex integrations and made the app live.
Feedback on 𝕏 and Telegram