About Us — One Tone Line

Mobile game development team reviewing a playable build

Who we are A development studio that takes client work seriously

We help startups, entrepreneurs and growing businesses turn validated ideas into focused, reliable mobile applications. Our services cover the complete development process — idea validation, project planning, user experience design, mobile app development, third-party integrations, testing, launch and ongoing technical support.

Our specialisation is mobile games. Casual, puzzle, arcade, idle and mid-core titles for iOS and Android, produced for publishers, studios and founders who need a team that can carry a project from a design document to a live product with players in it.

Alongside games we build practical business applications: customer booking apps, internal tools, service management platforms, e-commerce and subscription products, client portals and first versions of new startup concepts. Our solutions suit businesses launching their first application as well as companies improving or replacing an existing mobile product.

See Our Work How We Work

Our values Six things we argue about internally

These are not poster slogans. They are the positions we defend when a project is under pressure.

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Clarity First

A clear problem statement beats a long feature list. We would rather spend a week narrowing the scope than three months building the wrong thing.

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Honest Estimates

If a deadline is not realistic, you hear it during the estimate, not two weeks before the launch date.

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Craft

Feel, timing and polish are not the last task in the backlog. On a game they are the product.

insights

Evidence

Design opinions are useful; player data settles arguments. Everything we ship is instrumented from the first build.

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Respect for Players

We build monetisation that players tolerate on purpose. Dark patterns earn a quarter and cost a product.

loyalty

Long Relationships

Most of our work comes from clients we already shipped for. That only happens if the second project is easier than the first.

Our story From two contractors to a full production studio

2024

Studio founded

Two engineers taking mobile contracts, mostly rescuing projects that other teams had left half-finished.

2024

First full game production

A puzzle title built end to end for a European publisher — design, art, development and release under one roof.

2025

Art and QA brought in-house

Outsourcing the art pipeline kept costing us schedule. Building it internally cut production time on every project that followed.

2026

LiveOps and support practice

Clients kept asking who would run the game after launch. We built a team whose only job is what happens after release day.

Today

A team of 24

Designers, engineers, artists, QA and producers working on client games and business applications from one studio.

Mobile game design and production planning

Capabilities One team, the whole pipeline

No hand-offs between agencies, no “that part is not ours”. Everything a mobile product needs is in the building.

Game design
Economy & balancing
2D & 3D art
Animation & VFX
UI/UX design
Unity & Godot
Native iOS & Android
Back end & APIs
Analytics
QA & device testing
Store release
LiveOps & support

62 Titles shipped to stores

4M+ Downloads across client products

Client feedback People who worked with us

“They cut our feature list in half during scoping and were right about every removal. The build shipped on the date we agreed, which had not happened to us before.”

Marek Dvořák

Head of Product, casual games publisher Czech Republic · March 2026

“We came with a rough concept and no technical team. They handled design, development and the store submission, and explained every decision in language we understood.”

Ana Ferreira

Founder, wellness startup Portugal · November 2025

“Our prototype was fun for thirty seconds. They rebuilt the progression around it and retention went up by a third. That is the whole review.”

Daniel Osei

Studio Director United Kingdom · January 2026

“Deterministic combat, server-authoritative PvP, a build every two weeks. Communication was the part that surprised me most — nothing was ever a surprise.”

Lena Bergström

Executive Producer Sweden · June 2026

“They automated a booking process that used to run on spreadsheets and phone calls. Our staff saved a day a week within the first month.”

Tomás Herrera

COO, service platform Spain · August 2025

Partnerships

Advertise & Collaborate

We are always open to new opportunities, high-impact collaborations, and tailored business partnerships. Whether you want to advertise your brand to our audience, launch a joint project, or book our professional services, we are ready to bring your ideas to life. Every business is unique, and we don't believe in one-size-fits-all solutions. Please reach out to us using the contact form below, tell us a bit about your goals, and our team will get back to you with an exclusive, custom-tailored proposal designed strictly for your budget and objectives. Let's build something great together.

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Tell us what you have in mind and our team will come back with a custom-tailored proposal.

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A Studio Built Around Finished Products