App Development Company for US and European Businesses

You have an idea for an app, or a process that needs one, but the road from idea to something people can download is full of decisions you should not have to make blind: which platform first, native or cross-platform, how payments work in each region, and what Apple and Google will reject. Plenty of agencies can show you mockups. Far fewer can show you an app in the store.

We start by scoping the smallest version worth releasing, then design it, build it, test it on real devices and publish it for you. Your app is built by a team that has already shipped to the App Store, Google Play, the Mac and Windows, with the live products to prove it, and we stay on after launch for the updates every app needs.

Time zones

India Standard Time is UTC+5:30 all year, with no daylight saving. That puts us 3.5 to 4.5 hours ahead of Central Europe, 4.5 to 5.5 hours ahead of the UK and 9.5 to 13.5 hours ahead of the mainland US. European mornings overlap our afternoons. With US teams we agree a regular call window at the start and keep everything else in writing, so work never waits on a meeting.

How you see progress

As installable test builds and private staging sites rather than slides: TestFlight for iPhone and Mac, Google Play testing tracks for Android, test builds for desktop software and a staging site for web projects. Decisions are written down, so nobody has to remember what was agreed on a call.

Scope, quote and changes

Before work starts you get a written scope and a fixed quote, with milestones agreed alongside it. If the scope changes, we price the change before doing it, so the final invoice holds no surprises.

Ownership and accounts

The contract sets out who owns the code, the designs and the store listings. We recommend that everything lives in accounts your business controls from the first day: your Apple and Google developer accounts, your code repository and your hosting.

Privacy law

If your product offers goods or services to people in the EU or UK, or monitors their behaviour, the GDPR and UK GDPR generally apply. Where we process that data on your behalf we do it under a written data processing agreement, with Standard Contractual Clauses, or the UK equivalent, covering access from India. US state laws such as California's CCPA may apply too. We collect as little as the product needs: Kapy Notes keeps notes on the device unless the user turns on end-to-end encrypted sync.

Accessibility

The European Accessibility Act has applied since 28 June 2025 to many consumer products and services sold in the EU, including e-commerce and banking. In the US, ADA claims regularly cover websites and apps. We plan for screen readers, larger text and colour contrast from the first design, because retrofitting them late costs far more.

Native Swift for Apple platforms

When an app has to feel completely at home on the Mac or iPhone, or needs deep access to the system, we build natively. Strata is written in Swift and downloads at 12 MB, with sizes that agree with Finder.

Flutter for several platforms at once

When one product has to reach iPhone, Android, Mac and Windows, a single Flutter codebase covers them. Kapy Notes ships on all four, and still uses platform features where they matter, such as Apple's speech recogniser on the Mac and iPhone and the system file picker on Android.

What we will not do

Wrap a website in an app shell and call it an app. Neither of our approaches bundles a browser engine, which can add a hundred megabytes before an app does anything useful.

A defined project

A new app, a rebuild or a piece of software with a clear goal. We scope it, quote a fixed price and deliver it in milestones you can test, through to the store release or the handover.

A product that keeps shipping

Most software needs a steady rhythm after launch: fixes, new operating system versions and new features. We plan releases with you and keep a changelog your users can read, as Strata, Maintainly and Kapy Notes each do.

Taking over an existing product

If another team built your app or software, we start by reviewing the code, the build setup and the accounts it depends on, then tell you plainly what to keep, fix or rebuild before you commit to anything.

Platforms

One platform costs less than two. Flutter can cover iPhone, Android and the desktop from one codebase, while a native build for each platform suits apps that live close to the system.

Accounts, sync and a server

An app that keeps its data on the device is simpler than one with sign-in, sync between devices and a server to run. Each layer adds design, build, testing and hosting work.

Payments

In-app purchases and subscriptions bring store rules, receipts, restores and refunds, and Apple's and Google's payment rules now differ between the US, the EU and other regions. Apps that sell physical goods or services take payment outside the stores, which needs a payment integration of its own.

Integrations

Connecting to your existing systems, a CRM, a calendar or a payment provider means building and testing each connection, and keeping it working when the other side changes.

Regulated data and accessibility

Health, finance and children's apps carry extra rules. Accessibility work for the EU or US market needs its own design and testing time, and is far cheaper planned in than added later.

Life after launch

Apple and Google ship a major operating system release every year, and apps need testing and often changes to keep up. Budget for updates from the start rather than treating launch as the finish line.