Splync v1.3 Is Quadrilingual

When Splync was first launched, it was just a monolingual app — available only in English — even though this blog is now published in 42 languages. My native language is Japanese, and I am even officially certified to teach it, having passed the Japanese Language Teaching Competency Test administered by the Japan Educational Exchanges and Services. However, English seems to be the most globally accessible language in today’s world, so I released the first version of Splync in English as an MVP (Minimum Viable Product). As I look around, many Japanese people do not seem very comfortable using English, so adding Japanese support felt completely natural to me. I also added French, which I used to speak with older people in Rwanda when I volunteered in water and sanitation as part of the Japan Overseas Cooperation Volunteers program. Additionally, I included Simplified Chinese, which I can somewhat read, simply to see how the app would look in a different writing system.

Splync v1.3 supports four languages: English, Japanese, French, and Simplified Chinese. When expanding Splync beyond English, I wanted to make language support as effective as possible without unnecessary complexity. Instead of chasing quantity, I focused on impact per language. English naturally covers the widest international audience. Japanese is my native language and represents a large domestic market where shared budgeting apps are still emerging. French, on the other hand, extends reach across multiple continents — not only France but also parts of Africa, Canada, and Europe. Lastly, Simplified Chinese opens access to one of the world’s largest online communities. Together, these four languages provide balanced global coverage — North America, Europe, Asia, and Africa — while remaining manageable for a solo developer to maintain. From a cost-benefit perspective, it’s the most efficient multilingual setup at this stage. Since this was my first attempt at app localization, the whole process was a valuable experiment for me.

In Splync, I use Apple’s built-in localization framework with .strings files for each supported language, storing all user-facing text in a structured format. Each piece of text is identified by a key — for example, "sign_up_button" — and assigned a language-specific phrase in each .strings file. In English, this might be "Sign Up", while the other files contain the appropriate translations. In this way, each .strings file acts like a parallel corpus, unified by shared keys. These keys dynamically control all displayed text in the app UI based on the user’s selected language. While the mechanism itself is relatively straightforward, maintaining a high standard of translation quality is a much more complex challenge. And of course — I don't speak as many languages as C-3PO!

For this version, I used ChatGPT-4o to translate all keyed text and manually reviewed as much as I could. As a solo developer, I plan to automate the translation workflow further using Python and the OpenAI API, just like I do for this blog. Localization is both a linguistic and technical challenge. A good translation isn’t just literal — it must account for tone, phrasing, and cultural nuance. I previously worked for a global academic translation and editing company, which taught me the value of human review in catching the deeper context and intent that AI alone may miss. UI constraints are another factor — sometimes a translated phrase simply doesn’t fit in a button or label. So localization is not only about language, but also about layout and design. Through trial and error, I will continue to improve Splync’s multilingual experience to make it more natural, consistent, and scalable. And this journey isn’t just about code or prompts — I’d love to involve user feedback to raise the quality even further. If you spot any unnatural or awkward translations, feel free to let me know. Your input is always welcome.

I used to work as a Customer Experience Manager in global companies, and I learned how essential it is to listen to users. That’s one of the reasons I want to support more languages — so Splync can understand and grow with more voices. At the same time, great services and products must protect the shared interests of their user communities. One person may say this, another may say that. Some requests can be solved through customization. Others may require compromise. Ultimately, how we move forward must align with our core vision. As I’ve said before: Splync is vision-oriented, user-focused, and community-based. I hope we can keep growing together — to make Splync the simplest budgeting app that helps make life a little happier.