Fourthie
A social platform for finding people to do things with. It brings sports, coffee, gaming and study plans together around a specific activity, time, place and group of people.
Explore the work: Fourthie →Startups & product teams · UK & Europe
iOS and Android apps, built and released at a fixed price.
We build mobile apps for startups and product teams in the UK and Europe, together with the backend, admin tools and integrations behind them. One small team covers the app, the API and the release, and you speak directly to the engineers doing the work.
SaaS MVP or mobile app: £8,000–£18,000Typical range. The fixed price is agreed in writing after a short discovery.
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A mobile app is three projects in one.
The app on the phone is the visible part. Behind it sit an API, a database, notifications, an admin panel for your team, and the App Store and Google Play release process. When these are split between suppliers, nobody owns the whole thing and delays sit in the gaps.
We build all of it as one scope, at one fixed price, with the same engineers from the first screen to the store release.
Who it’s for.
- Startups launching a product that customers mainly use on their phone.
- SaaS companies adding a mobile app to an existing web product.
- Businesses replacing paper or spreadsheet processes with an app for staff on the move.
- Teams with an unfinished app that needs to reach the stores.
What you get.
- Cross-platform apps with React Native, or native iOS with Swift when the product needs it.
- Backend, API, database and an admin panel for your team.
- Accounts, push notifications, payments and location features as required.
- Connections to your web product, CRM or third-party services.
- App Store and Google Play submission through your own developer accounts.
- Documentation and code handover.
What’s not included.
- App Store and Google Play review decisions and timelines.
- Developer account fees, hosting and third-party service costs unless included in the quote.
- Brand identity and marketing assets unless agreed in the scope.
- Ongoing support unless agreed separately.
How it works.
- 01 · Discovery call30 minutes, free. Who uses the app, where and why.
- 02 · Scope and quoteScreens, user flows, technical plan and a fixed quote.
- 03 · BuildTest builds on your own phone every week through TestFlight and Google Play testing.
- 04 · ReleaseStore submission, deployment, documentation and handover.
Timeline and price.
Mobile apps typically cost £8,000–£18,000, including the backend and admin panel they need. More complex apps start from £15,000; the size of the backend and the number of integrations usually decide where a project sits.
The price and delivery plan are fixed in writing after a short discovery. Larger builds can start with a paid scoping phase, credited against the build. Builds are paid 50% at the start and 50% on delivery.
- Typical app (£8,000–£18,000)One cross-platform app for iOS and Android with sign-in and the screens for one main user journey, push notifications, a backend with a simple admin panel, and store submission.
- More complex apps (from £15,000)Real-time features such as chat, offline sync, payments with custom rules, several user roles or native Swift work.
- Not included unless agreedBrand and marketing assets, store fees, and ongoing support after release.
Work behind the service.
Fourthie is our own social app for web and mobile, built with React Native. Momentrio brings event photos from attendees into one shared space. WerkRechner is a native SwiftUI app in pre-release development.
Momentrio
Brings photographs from an event into a shared digital space. Attendees can contribute their pictures so the event’s images can be collected and viewed together.
Explore the work: Momentrio →WerkRechner
A German-language work and calculation app. It combines a scientific calculator with tools for tax, discounts, profit margins and unit conversions.
Explore the work: WerkRechner →What should you send us?
- Who will use the app, and what they need to do on their phone.
- Whether you need iOS, Android or both, and any device features involved.
- Existing designs, web product, API or backend.
- Your target release date and budget range.
Questions before we start
Native or cross-platform?
For most products we recommend React Native: one codebase for iOS and Android, and quicker changes. We build native Swift when the app depends on device features or performance that need it. We make the recommendation during discovery.
How much does it cost to build a mobile app?
Most mobile apps we build cost £8,000–£18,000, including the backend. More complex apps start from £15,000. We fix the price after a short discovery.
Will you publish the app to the App Store and Google Play?
Yes, through your own developer accounts, so the listings belong to you. Apple and Google make the review decisions, so we plan time for them in the release.
Can you add an app to our existing web product?
Yes. We review your API, sign-in and data first, then scope the app and any backend changes it needs.
Do we have to pay for scoping?
No. The discovery call and the quote are free for most projects. For larger builds we may suggest a paid scoping phase: a written scope, technical plan and a first working slice. Its cost is credited against the build.
Who owns the code and the store listings?
You do. The repositories, store listings and cloud accounts are in your name, and the code is handed over with documentation.
Who you’ll work with.
- A UK limited company.You contract with Fortuna Supply Ltd, registered in England and Wales (company no. 15831822). SaaSAppStudio is its trading name. Quotes are in pounds sterling.
- Working hours that overlap with yours.Our engineers work from İzmir, Türkiye, two to three hours ahead of London, so most of the UK working day is shared. Calls and reviews happen live, not overnight.
- A fixed price, agreed up front.After a short discovery we agree a written scope and a fixed price. If the scope changes, we price the change before starting it.
- Direct contact with the engineers.You speak to the people building your product, not to an account manager passing messages on.
- You own what we build.The code, repositories and service accounts are set up in your name and handed over with documentation.
The studio’s founders are Halis Erdem Kömeç (engineering) and Merve Kömeç (partnerships and delivery). Meet the studio →