Custom Development
App development company in London for iOS, Android and web
Custom apps taken from a clear scope to the App Store and Google Play, with support after launch. A fixed written quote after a free call.
In short
App development is the design, building and publishing of software for phones, tablets and the web. APPS 365 is a UK company with a registered office in London that builds custom iOS, Android and web apps, handles store submission and supports them after launch, with a fixed written quote before work starts.
What stalls most app projects
App projects often go wrong before any code is written. The cost is unclear, the scope keeps growing, and nobody has planned for life after launch.
You cannot get a straight answer on cost.
We scope the app with you, then give you a fixed written quote before any work starts.
You are not sure what to build first.
Discovery separates what the first version needs from what can wait, so you start with something you can launch.
You have heard of agencies that disappear after launch.
Support and updates are discussed from the start and set out in your quote, so you know who looks after the app.
Store rules and rejections feel like a black box.
We prepare the listing and privacy details Apple and Google ask for, and deal with anything raised in review.
What you get from a custom app build
iOS, Android and web in one place
One supplier for the phone app, the web version and the systems behind them, so nothing falls between separate suppliers.
A clear scope first
You know what is being built, what is left out and what it will cost before work starts.
Working builds as we go
You try test versions on real phones during the build, so you can change course before a change gets expensive.
Store submission handled
We prepare and submit your App Store and Google Play releases, and respond to anything the reviewers raise.
Designed for data protection
We design for UK GDPR from the start, collecting only what the app needs and limiting who can see it.
Support after launch
Phones, operating systems and store rules keep changing. We can keep your app up to date and add to it, on terms set out in your quote.
What is included
Exactly what you get is set out in your written quote. A typical app project covers:
- Discovery: your users, your goals and a written scope for the first version
- Screen designs, and a clickable prototype where it helps
- iOS and Android builds, plus a web version if you need one
- The back end: accounts, data, admin and connections to your other systems
- Testing on real devices, with test versions for you to try
- App Store and Google Play listings, submission and review handling
- Crash and usage reporting, handover notes and agreed support
Native, cross-platform or web: which do you need?
No option is right for every app. It depends on what the app has to do, and we will explain the trade-offs in plain English.
| How it is built | Good for | Watch out for | |
|---|---|---|---|
| Native | Separate code for iOS (Swift) and Android (Kotlin) | Heavy use of the camera, sensors or graphics | Two codebases to build and maintain |
| Cross-platform | One shared codebase, using a framework such as React Native or Flutter | Most business and consumer apps that need both platforms | Some device features may need extra native work |
| Web app | Runs in the browser, with no store listing | Portals, dashboards and tools people use on a computer | Less access to phone features and no store presence |
What affects the cost of an app
We do not publish a price list, because two apps built on a similar idea can be very different jobs. The things that move the price most are how many platforms you need, how many screens and types of user there are, whether people log in or pay, which other systems the app connects to, and how much sits behind it in an admin area.
Then there are costs after launch. Budget for hosting, third-party services, store developer accounts and updates, because phones and store rules keep changing. We will talk these through before you commit.
From idea to the App Store and Google Play
- 1
Free call
We talk through the idea, your users and what the app has to do. No obligation.
- 2
Written quote
You get a fixed price, the scope and the timetable in writing before any work starts.
- 3
Discovery and design
We agree the first version in detail. You get a written scope and screen designs to sign off.
- 4
Build and test
We build in stages and test on real devices. You try working versions as we go.
- 5
Store submission
We prepare the listings and privacy details, submit to Apple and Google, and handle any questions from review.
- 6
Launch and support
We go live and keep the app up to date on the terms in your quote.
We ship our own apps
These are our own products, not client work. We do not have client case studies to show here yet, so judge us by what we have built and published ourselves.
Pricing guide
Each app is priced after a free call, with a written fixed quote before work starts. We do not publish a from price, because the range of possible apps is too wide for one number to mean much. We will also talk you through the running costs to expect after launch.
- Priced after a free call
- Fixed written quote before work starts
- Running costs discussed before you commit
Why APPS 365
UK-based
APPS 365 LTD is registered in England and Wales, with a registered office in London.
Microsoft ecosystem specialists
We publish SharePoint and Microsoft 365 apps on Microsoft Marketplace, so we build on this platform every day.
We ship our own products
Apps, games and SaaS platforms of our own, live for anyone to try. ComponentSource Top 100 Publisher 2022, 2023 and 2025.
A fixed quote first
A free call, then a written quote before any work starts, so you know the cost and scope.
Building a mobile game rather than an app? Our games studio, APPS 365 GAMES, covers those.
Mobile games on apps365.gamesFrequently asked questions
How much does it cost to build an app in the UK?
It depends on the scope, so we price each app after a free call, with a written fixed quote before work starts. The biggest factors are the number of platforms, screens and types of user, plus logins, payments and connections to other systems.
How long does it take to build an app?
It depends on the size of the first version, so the timetable is agreed in your written quote. A tightly scoped first release is usually the quickest route to the stores. Apple and Google also review each app before it goes live, so we plan for that step.
Should I build for iOS, Android or both?
Build for wherever your users are, and for both if your audience is the general public. If you know most of your customers use one kind of phone, launching there first can keep the first version smaller. A shared codebase can make both practical from the start.
Is a native or cross-platform app better?
Cross-platform suits most business and consumer apps, and native suits apps that lean heavily on the camera, sensors or graphics. We recommend one after hearing what your app has to do, and we explain why.
How do I get my app on the App Store?
You need a developer account, a finished build, a store listing and privacy details, and then Apple reviews the app before it goes live. Google Play works in a similar way. We prepare and submit the release for you and deal with any questions that come back.
What happens if Apple or Google rejects the app?
We read the reason given, fix what has been raised and resubmit. Rejections often come down to missing privacy details, incomplete information or a feature that breaks a store rule, which is why we check those rules at design stage.
Who owns the app and its code?
Code ownership is agreed in writing in your quote before work starts, so you know where you stand from the beginning. The same goes for hosting location and data residency. Ask us on the call if you have a specific requirement.
Do you support the app after launch?
Yes, we can keep your app working and add to it after launch, on terms set out in your quote. Apps need regular attention because iOS, Android and store rules keep changing.
Tell us about the app you want to build
A free 30-minute call, then a fixed written quote. No obligation.
