Mobile App Design: UX and UI for iPhone and Android

What good app design means for a small business

A good business app does a few things very well. A customer opens it to book, reorder, check a status or claim a reward, and should be able to do that in seconds without thinking about the interface. Mobile app design is the work that makes that possible: deciding what goes in the app, how people move through it, and how each screen looks and behaves.

Apptavio designs apps for iPhone and Android for small and medium-sized businesses. Design is part of every app we build, and we start with something you can actually tap through rather than a slide deck.

Who this is for

• Businesses planning a first app who want to see and test ideas before development starts.
• Businesses with an existing app that is hard to use, looks dated or no longer matches their brand.
• Teams who have a clear idea of features but need help turning it into usable screens.

Our design approach

1. Start with tasks, not screens

We begin by listing the jobs your customers come to do. For a dog groomer that might be "book the next groom" and "check my dog is ready"; for a garage, "approve a quote" and "see when my car will be done". The home screen and navigation are then built around those few tasks.

2. Make it feel native

People use dozens of apps every day and expect familiar behaviour. We follow Apple's Human Interface Guidelines on iPhone and Material Design conventions on Android for things like navigation, system controls, gestures and permissions. Your brand stays consistent across both, while the details feel right on each platform.

3. Design every state

Real apps are not just their best-case screenshots. We design empty states (no bookings yet), loading states, errors (no connection, payment declined), permission prompts and confirmation messages, because these are where users get stuck.

4. Build in accessibility

We use the Web Content Accessibility Guidelines (WCAG) as a reference: sufficient colour contrast, text that scales with the system font size, touch targets that are easy to hit, clear labels for screen readers and no information conveyed by colour alone. Accessible design is better design for everyone, including customers using your app outdoors or one-handed.

5. Create a design system

We define colours, typography, spacing and components as reusable tokens. This keeps the app consistent and makes future features faster and cheaper to add.

See your app design before you buy

You do not have to imagine what your app could look like. We can build a free, personalised, interactive concept from your existing website, using your business name, branding colours, imagery and the services or products on your site. You open it in a browser on your phone or computer and tap through screens like the home screen, booking or shopping flows and a customer profile.

The concept is a prototype to start the conversation — features are simulated and it is not a finished app. Every concept is reviewed by a person before we send it, and there is no obligation. We email you a private link when it is ready.

What you receive

• Agreed user journeys for the main tasks.
• An interactive prototype of the key screens.
• High-fidelity designs for every screen and state in scope.
• A component library and design tokens used directly in development.
• Store assets guidance: app icon, screenshots and preview text.

How design fits into the project

1. Free concept from your website.
2. Scope and priorities — we agree which journeys matter most for launch.
3. Prototype and feedback — you try the prototype on your phone and we refine it.
4. Final designs for all screens and states.
5. Build in React Native, Expo and TypeScript, with design and development working from the same components.
6. Review on real devices before submission to the App Store and Google Play.

What affects the cost

Design is normally included in a custom app project; apps start from €1,499 (indicative starting price). The design effort depends on:

• Number of screens and journeys.
• Complexity — multi-step flows such as booking with staff selection, or checkout with variants.
• States and edge cases each screen needs.
• Brand work — whether you have brand guidelines or need help adapting your identity for mobile.
• Design system depth and how much the app will grow.
• Accessibility testing and content work, such as alternative text.

Honest limitations

• Good design cannot fix a feature nobody needs. We will sometimes recommend doing less.
• Apple and Google review apps against their own guidelines, including design-related rules. Following them closely helps, but approval is their decision.
• Accessibility depends partly on content: images need descriptions and text needs to be clear. We help, but some of that work is yours.
• Store screenshots and descriptions also influence downloads. We provide guidance, but results in the stores are not guaranteed.