Portfolio

The Challenge
 

A Swedish health and wellness app — covering workout tracking, nutrition logging, meditation and sleep analysis — had grown to 4 million users across Scandinavia and the UK and was preparing a Central European expansion starting with the Czech Republic.

The app's brand voice was a core part of its product: warm, motivating and personal — the tone of a knowledgeable friend rather than a clinical health platform. The challenge was not simply translating the words but preserving that voice in Czech, where the language has formal and informal registers that need deliberate handling. Using the wrong register in a wellness app — too formal, too stiff — kills the warmth that makes the product work.

A further complication was the App Store and Google Play listing: Czech App Store descriptions and keyword fields required careful localisation to maximise organic search visibility in the Czech store, not just a word-for-word translation of the English listing.

The client also needed AI post-editing — they had used an AI tool to produce a first draft of the lower-priority content to reduce costs, and needed a native expert to bring it up to the quality standard of the hand-translated content.

What We Did
 

Czech Localization began with a brand voice workshop with the client's content team to define the Czech tone of voice parameters: informal register throughout, motivating but not aggressive, warm and personal without being patronising. These guidelines were documented and applied consistently across all content.

The project covered five content areas:
 

• Core app UI — all screens across workout, nutrition, meditation and sleep modules including unit conversions, date formats and Czech-specific health metric conventions (4,200 words — hand translated)

• Onboarding and personalisation flow — goal-setting screens, health profile questions and personalised recommendation copy, where tone is most critical to first-impression retention (1,400 words — hand translated)

• Push notifications and in-app messages — motivational prompts, reminder copy, achievement messages and streak notifications requiring punchy, energetic Czech (900 words — hand translated)

• App Store and Google Play listing — title, subtitle, description and keyword fields optimized for Czech store search behaviour (600 words — hand translated)

• Secondary content — FAQ, settings descriptions and legal summaries (2,700 words — AI post-edited)

The AI post-editing workstream involved a full review of the machine-translated draft, correcting terminology, register inconsistencies and unnatural phrasing throughout. A quality comparison report was provided showing the volume and nature of changes made, which the client used internally to assess their AI tooling.

The Results
 

41%Higher D7 retention

Czech users vs prior CEE launches without native localization

#3 Top Health app

Czech App Store Health & Fitness chart within 30 days of launch

8 Days to delivery

Full 9,800 word project across 5 content areas