Mobile app vs web app: which should you build?

A web app is software that runs in a browser at your own web address. There's nothing to install, you share it with a link, and when we deploy a change everyone has it at once. Gmail is a web app. So is your online banking, and so is most of the software you use at work without thinking about it.

A mobile app is a program installed on a phone from the App Store or Google Play. It gets an icon, it can run without a connection, it can use the camera and the GPS and Bluetooth without asking the browser's permission first, and every change you make goes to Apple or Google for review before your customers see it.

There's a third option people forget. A progressive web app is a web app the phone will let you add to the home screen. It gets an icon, opens full screen with no browser bar, caches enough to survive a lost connection, and since iOS 16.4 it can send notifications on iPhones as well as Android. No store, no commission, no review queue. It's the middle option, and for a lot of businesses it's the right one.

If you plan to sell anything digital inside a mobile app, this is the paragraph that matters most. Apple and Google take a commission on digital purchases made in an app: 30% as standard, dropping to 15% for smaller developers and for subscriptions after the first year. On a £10 monthly subscription that's up to £3 of every payment, against roughly 21p through Stripe on the web.

Physical goods and real-world services are exempt. Deliveroo pays no commission on your curry and a plumbing app pays none on the boiler, because the store only takes a cut of things consumed inside the app. So a shop or a booking system can live happily in an app store. A subscription product needs the sums done first.

This is also the part of the industry moving fastest. A US court ruling in 2025 forced Apple to let apps link out to their own checkout there, and the EU's Digital Markets Act pushed both companies into similar changes. The direction is loosening, but the detail differs by country and keeps shifting, so check where it stands in the month you build rather than trusting a blog post from last year, this one included.

Most first builds should be a web app. It costs less, it changes in minutes while you're still learning what customers actually do, and it doesn't ask anyone to install anything before they'll try it. When the usage is there, a mobile app gets added on top of the same backend rather than starting again. We'd rather build you the £1,500 version that works than the £3,000 version that guesses.

We build both, either way, and it's the same two people doing it. Lucas writes the code, front to back, so the person you describe the idea to is the person who builds it. Piers came from law, which is why contracts, data protection and what happens to your data are settled before the build rather than after it. You own the source code on delivery, and there's no per-seat licence quietly renting your own software back to you.

Everything is quoted fixed and in plain English before we start, and if your idea is bigger than your budget we'll tell you which part to build first rather than quoting for all of it and hoping.