How much does it cost to build a mobile app?

People are usually surprised by two things when they ask this: how much more an app costs than a website, and how much of the cost has nothing to do with the screens you tap on. Here's where the money actually goes, and the decisions that move the number most.

Why an app costs more than a website

A website is one product that runs in every browser. A mobile app is usually three: an iOS app, an Android app, and the backend server they both talk to — the part that stores your data, handles sign-in, sends notifications, and does everything the phone shouldn't do on its own. Each piece has to be built, tested, and kept working. Then the two apps go through App Store and Play Store review, which adds time and its own rules to follow.

What drives the cost

• One platform or two. Shipping iOS and Android together is the single biggest cost multiplier. If your audience skews heavily to one, starting there is often the right call.
• Native or cross-platform. Native apps (SwiftUI for iOS, Kotlin for Android) give the best fit and performance but mean two codebases. Cross-platform tools share one codebase across both stores and can reuse a web app you already have. I've shipped both — it's a tradeoff we pick in discovery, not a default.
• The backend. Accounts, roles, data sync, push notifications, payments, and an admin panel for you to run things from. This is often half the project, and it's invisible in the app store screenshots.
• Device features. Camera, location, offline mode, Bluetooth, and background tasks each add real engineering and testing across many devices.
• Integrations. Payments, a CRM, a calendar, an existing system of record. Each is a boundary to build and maintain.
• Design. Apps live under a stricter microscope than websites — people compare yours to the polished apps they use every day. Good design isn't optional here.

The approach that keeps costs sane

One backend, several front doors. Instead of building a web product and a mobile product as separate systems, I build one backend and put a web app and the mobile apps on top of it. Features and data stay in sync everywhere, and adding a second platform later is a fraction of the original cost because the hard part already exists. That's how the Kappa Sigma platform runs: a web app plus native iOS and Android clients on a single shared backend serving hundreds of chapters.

Ongoing costs after launch

An app is never quite finished. Budget for: developer program fees (Apple charges an annual fee, Google a one-time one), hosting for the backend, any paid services the app relies on, and — most importantly — updates. iOS and Android release new versions every year, and an app that isn't maintained eventually breaks or gets pulled from the store. Plan for a light maintenance retainer, or an internal team that owns the code.

How to build one without overspending

• Ask whether you need an app at all. A well-built web app works on every phone, installs to the home screen, and skips the app stores entirely. If you don't need push notifications, the camera, or offline use, start there.
• Start with one platform. Prove the product with the audience you have, then add the second platform on the same backend.
• Ship the smallest useful version. The first release should do one job well. Every screen you defer is money you keep and a decision you get to make with real users instead of guesses.
• Own the code. Whoever builds your app, make sure the code, the store accounts, and the backend are yours. It's the difference between hiring help and renting your own product.

Get a real number

Discovery is free. Tell me what the app needs to do and who it's for, and I'll tell you honestly whether it should be a mobile app, a web app, or both — and, after discovery, give you a fixed scope and price.