How much does an app cost?

A custom app for iOS and Android, designed, built and published on the stores, costs between €10,000 and more than €50,000. The price is set not by the kind of app, but by what it has to do:

• An app with the essentials: €10,000 to €20,000, 2 to 3 months. A few screens, designed for phones, and users who sign up and sign in. The backend is an off-the-shelf one, such as Strapi, which is configured rather than programmed: from its dashboard, your team manages the content and the users.
• With a custom backend: €20,000 to €50,000, 3 to 5 months. When the app needs its own logic, such as points and rewards or notifications based on what each user does, and a dashboard built around how your team works. It usually connects to common services, such as Google or Apple sign-in, maps or a payment gateway.
• With corporate systems or demanding requirements: from €50,000, 5 months or more. Connections to your company's ERP, CRM or corporate sign-in, an offline mode that syncs the data when coverage returns, or a backend built for many simultaneous users or with stronger security, such as health data requires.

Watch out for what looks simple. A catalogue or an event app sounds small, but as soon as it includes a loyalty programme or connects to your systems, it moves into the second or third group. What costs money is what you ask the app to do, not what you call it.

The ranges include design, development for iOS and Android, the backend and dashboard when needed, and publishing on the stores. Servers, maintenance and the Apple and Google developer accounts are extra; we explain them below.

What weighs most is not the number of screens, but what sits behind them:

• Backend. If the app has users or content your team manages, it needs a backend: a server, a database and a dashboard. An off-the-shelf one, such as Strapi, is configured rather than programmed, and it's enough for many apps. When the app needs its own logic, the backend is custom-built, and it can be as sophisticated as the app requires: performance for many simultaneous users, stronger security, a tailored dashboard. Each of these adds cost, and it's the part you don't see in the app.
• Integrations. Connecting to common services, such as Google sign-in, maps or a payment gateway, doesn't cost the same as connecting to your company's ERP or CRM. The former are built for it and well documented. A corporate system is usually tailored to each company, sometimes without a ready-made API, and each connection has to be studied, like the one for the Compo Expert catalogue, synced with their systems.
• Offline mode. The app keeps working without coverage and syncs the data when it returns, like the questionnaires in Your Decision. You have to decide which data is stored on the phone, what happens if two people change the same thing and how the app shows what is still to be sent, and all of that is built into both the app and the backend.
• Tablets. An app designed for phones also opens on a tablet, but it doesn't make use of the screen. Designing it for tablets means rethinking every screen for that size, and even more so if it has to rotate between portrait and landscape or work in windows of any size on iPad, such as split screen or floating windows.
• Screens and flows. The more screens and the more different paths (user profiles, states, errors), the more design, development and testing.
• Design. A custom interface, validated with a prototype, costs more than adapting an existing style, and it shows in how the app feels every day.
• Other requirements. Accessibility, several languages or health data add work to every part of the project.

Do iOS and Android cost twice as much? No. We work with React Native: one codebase for both platforms, with native performance and look. Building both costs a little more than building just one, because you test and publish on both, but nowhere near double.

An app isn't finished when it's published. Plan for three costs:

• Maintenance. Apple and Google release new versions of iOS and Android every year and ask apps to keep up: Google Play stops offering apps that don't to new users on recent phones. Our basic maintenance, from €99 a month excluding VAT, keeps the app up to date on the stores through these small updates. If you want it to include fixes, support or improvements, the price depends on what's included.
• Servers. The backend needs hosting, which is separate from maintenance and depends on usage: an app with a hundred users is not the same as one with a hundred thousand.
• Developer accounts. Apple charges $99 a year and Google a one-off $25. We explain how to set them up in the next section.

New features, the evolution of the app, are quoted separately, as a small project.

To publish an app you need two developer accounts: one with Apple, for the App Store, and one with Google, for Google Play. They are normally yours, in your company's name, so the app stays yours even if you change provider one day. You sign up, invite us as users and we set everything up: the store listings, certificates, privacy forms and every submission for review.

Apple Developer Program: $99 a year (Apple charges it in local currency at checkout). To enrol as a company, Apple asks for:

• A legal entity: a trade name is not enough.
• A D-U-N-S number.
• A public website on your own domain and an email address on that domain.
• Someone who can sign on behalf of the company, with an Apple Account with two-factor authentication.

Apple reviews the details before approving the enrolment.

Google Play Console: a one-off $25. As a company, Google asks for the D-U-N-S number, the company's website and phone number, a contact with email and phone and, sometimes, an ID document. Open it as an organisation rather than a personal account: new personal accounts have to run a closed test with at least 12 people for 14 days before they can publish.

The D-U-N-S is a number that identifies your company, issued by Dun & Bradstreet. It's free, but it can take up to a week. Many companies already have one without knowing it: Apple has a lookup tool to check.

Our advice: start the sign-up at the beginning of the project, not the end. Between the D-U-N-S and the Apple and Google reviews, a couple of weeks can go by, and it's better if they don't delay the launch.

• Start with a first version. What the app needs to be useful, published soon; the rest, once you know what people actually use.
• One codebase for iOS and Android. With React Native you don't pay for two apps.
• Prototype before coding. Changing a screen in the prototype takes minutes; changing it in the finished app takes days.
• Decide what you won't build. Every “just in case” feature costs money to build and, later, to maintain.
• Compare what each quote includes, not just the figure. If the cheapest one leaves out the backend, the dashboard, testing or publishing, you'll pay for it later.

We start with a 30-minute call to understand what you want to achieve, who the app is for and what constraints there are. Then we send you a proposal with scope, timeline and budget, with no small print.

For small projects, the price is fixed for the whole project. For larger ones, we fix it by phase (design, development, launch): each phase has its scope and its price, and if you want to change something halfway, we tell you what it costs before doing it. From the start you have test versions on your phone so you can see how the app is coming along.