App Design Agency London

Biotik is an app design agency in London designing iOS, Android and web apps that people find easy to use and teams find fast to ship. We cover the whole experience — UX, UI, interactive prototypes and a design system — with senior designers on the work and offices in London and Tallinn.

A great app isn’t a stack of pretty screens. It’s a clear flow, a confident interface, and a system that keeps every new feature consistent. We design for that, and we test it before your engineers write the code.

What we design

• App UX — onboarding, navigation and the core flows that decide whether people stay
• App UI — a polished interface that respects each platform’s conventions
• Prototypes — interactive, testable versions before build
• Design systems — components and tokens your developers build against

iOS, Android and web

We design to the conventions of each platform while keeping one coherent product and brand across all of them — so an iPhone user, an Android user and someone on the web app all feel like they’re using the same considered product. The handover is a design system engineering can build against, not a folder of static mockups.

How we work

Most app work runs as a fixed-scope project or an embedded engagement, with senior designers involved throughout. Based in London and Tallinn, we’re on UK time with a Baltic engineering-design culture — close, fast and aligned. If you want the underlying craft, the same thinking runs through our UX/UI design and product design services.

Already have an app that isn’t performing? A UX audit pinpoints where users struggle and what to fix first, and pairs naturally with focused onboarding and activation work to keep the users you win.

Common app problems we fix

Most apps don’t fail on looks — they leak users in the same few places. These are the issues we’re brought in to solve most often:

• A first run that loses people — onboarding that explains features instead of getting users to their first win
• Navigation people get lost in — too many tabs, unclear hierarchy, buried core actions
• Inconsistent screens — a product that feels like three apps because there’s no design system underneath
• Forms and permissions asked too early — friction before the user sees any value
• A web app and mobile app that feel unrelated — no shared language across platforms

From prototype to shippable design

We work in short cycles you can see and steer. Early on that means clickable prototypes to pressure-test the core flow before engineering commits; later it means production-ready screens and a documented design system with components, states and tokens. You finish with something a developer can build against on day one — not a folder of static images that need re-interpreting. For teams scaling fast, that system is what keeps the tenth screen as considered as the first, exactly as we describe in our design systems playbook.