Fintech app development for iOS and web
Fincode builds iOS and web apps for finance data and analysis, from a written scope to a tested release. The one real example is Fiva, our own investment analytics app, in beta on iPhone and in Turkish only. Fiva does not place trades, so it shows data and analysis work, not order handling.
What Fiva is
Fiva is Fincode's own product, not client work. It is in beta for iPhone through TestFlight, the app is in Turkish only, and its browser version, Fiva Web, is still being prepared. Fincode has no client projects to cite, so this is what we can show you.
It brings stocks on BIST, NASDAQ and European exchanges, mutual and pension funds, ETFs, gold, FX and commodities into one markets screen, with macroeconomic data, charts, watchlists, price alerts and fund comparison tools around them.
What Fiva does not show
- Order placement: Fiva does not execute trades
- Work on payments, custody or identity checks
- Delivery to a client: it is our own product
If your app needs any of these, raise it in your brief. We say in writing whether it fits.
Product decisions you can check in Fiva
These are choices any finance data app has to make. The Fiva case study goes further into the engineering.
Estimates next to their record
Fund prices are published at the end of the day. Fiva estimates each fund's daily return before then and shows the historical accuracy rate beside the estimate, with the time the price becomes final. Estimates are model-based, may be wrong and are not buy or sell recommendations, and past accuracy does not guarantee future accuracy.
A plain statement of how current the data is
The app's “Data and Delays” section says which data is real-time and which is delayed. Data agreements decide what can be shown with which delay; the product's job is to let users see it.
Many sources behind one screen
The daily summary gathers the economic calendar, company disclosures from KAP (Turkey's public disclosure platform), dividend and capital increase calendars, IPOs and news ranked by importance. Across markets, that means reconciling symbols, trading hours, holiday calendars and corporate actions into one model.
User posts under written rules
Fiva's investor community has terms that prohibit offers of unauthorized investment advice, paid signals or portfolio management. Posts belong to their authors and are not verified by Fincode.
An AI assistant with limits
Fiva AI can take into account the portfolio information users enter, and it does not give buy, sell or personalized investment recommendations. Its answers may be wrong and are not investment advice.
Who this suits
Founders with a finance data or analysis product
A portfolio tracker, a fund or stock screener, a calendar or a set of calculators, where the value lies in the data and how it is shown.
Companies adding an app to an existing business
You already hold the data rights or the license, and you need an iOS or web client for your own users.
Teams with a backend and no app
Your API exists, and you need the screens on top of it, with delays, errors and stale data handled properly.
Not a fit
An app that would hold customer money, send orders for other people or tell users what to buy. Those need a license or a licensed partner first. If you are that licensed firm, send the scope and we will say in writing whether it fits. Signals, copy trading and running other people's accounts stay out in every case.
Features, and the question each one raises
A feature that looks small on a screen can change what your company legally does. These questions go in the scope, for your lawyer, before design starts. Our guide to fintech app development cost shows what they do to a budget.
| Feature in the app | Question to settle first |
|---|---|
| Prices and charts | Does your data license cover display to these users, at this delay, and what label must the screen show? |
| Model-based estimates or rankings | Could a user read them as a recommendation? What does the screen say about accuracy and limits? |
| Holdings the user types in | Which personal data rules apply where your users are, and where is the data stored? |
| Read-only access to a user's exchange or broker account | Do the platform's terms allow third-party access? Who holds the key, and how does the user revoke it? |
| Sending orders | Who holds the license? In Türkiye, receiving and transmitting orders in capital market instruments is an investment service under Article 37 of Capital Markets Law No. 6362, and Article 39 reserves those services for authorized investment firms |
| Holding money or moving payments | Which payment or e-money license applies, and which licensed provider sits behind the app? |
| Holding crypto or keys | Which custody rules apply? Apple adds that wallet apps must come from developers enrolled as an organization (guideline 3.1.5(i)) |
| Telling users what to buy, or letting them copy others | Advice and portfolio management rules can apply. Fincode does not build these features |
What is checked first
What the app does, in legal terms
Each feature you describe is read against the table above. Showing data, transmitting orders, holding assets, moving money and giving advice are different activities, and several need a license. Fincode does not give legal advice; the scope lists the questions for your lawyer.
Who publishes it
Apple's App Review Guidelines (opens in a new tab), read on 5 November 2026, say apps used for financial trading, investing or money management should be submitted by the financial institution performing those services, with the licenses needed where the app is available (3.2.1(viii)). So the publisher is settled before the first screen.
Whether you may show the data
Free access is rarely a right to show data in a commercial app. Real-time exchange data is often charged per user, and delayed data can require a label, so data can be the largest recurring cost. See stock market data APIs.
What the first release has to prove
iPhone, web or both. A web release can change without store review and reaches any device with a browser; a native iPhone app goes through review and gets native push notifications and a store listing. We ask what you need to learn first and scope the smallest release that answers it.
Your country and the platform's terms
This applies if the app connects to an exchange or broker. For customers outside Türkiye, which platforms can be used depends on the law of your country and the platform's terms. For customers resident in Türkiye, we work with platforms on the Capital Markets Board's list that offer an API; being listed does not mean a platform is authorized.
Technical decisions in a finance app
Each of these goes in the written scope, because each is expensive to change later.
Vendor keys stay on the server
A key shipped inside an app can be extracted. The app talks to your backend, and the backend talks to data vendors, holds the keys and enforces who may see which data.
Alerts run on the server
Apple's documentation (opens in a new tab) says the system decides when to launch a background task, so a price alert cannot depend on the app being awake. Conditions are checked on the server and delivered as push notifications.
Old app versions keep running
A web client changes when you deploy; an iPhone client changes when each user updates. The API stays compatible with versions still in use, and the tests include an old client against a new server.
Exact numbers, local formats
Money and prices use decimal types, so binary rounding errors do not reach totals. Formats follow the user's locale: 1.234,56 in Turkish and 1,234.56 in US English.
Stale data is labeled
Phones lose their connection. Cached values stay on screen with their age, instead of a blank page or a number that looks live.
Store rules built in from the start
Apple requires in-app account deletion if an app supports account creation (5.1.1(v)), and filtering, reporting, blocking and published contact details for user-generated content (1.2). Outside testers on TestFlight (opens in a new tab) need a build approved by App Review. These are screens and backend work, so they are in the scope from the first day.
Security as a list of practices
OWASP MASVS (opens in a new tab) gives the control areas, including storage, cryptography, authentication and network communication. Tokens go in the device keychain, and authorization is checked on the server. Fincode claims no certification, and an independent penetration test is a separate decision for you to make.
What you receive
- A written scope, with a list of questions for your lawyer
- A screen and data map: each screen, its source, its delay and what the user is told
- Screen designs for the agreed flows
- An iOS app delivered through TestFlight on your own developer account, a web app, or both
- A backend API with data adapters, on your own server or cloud account by default
- A test report: lost connection, delayed source, expired session, old app version against a new API
- A store submission checklist: privacy details, review notes and a test account
- Technical documentation
What Fincode does not do
- Buy or sell prompts, recommended portfolios or signals inside an app
- Copy trading, or features for following other users' portfolios
- Running a platform that places orders for other people
- Holding customer money or keys
- Supplying or reselling market data: your company holds the license
What a screen and data map looks like
One row per screen. It shows at a glance which data agreement each screen relies on and what the user is told about it.
| Screen | Shows | Source | The user is told |
|---|---|---|---|
| Watchlist | Last price and daily change | [licensed data vendor] | [delay stated in your data agreement] and the time of the last update |
| Fund detail | Model-based estimate | [your model] | That it is an estimate and may be wrong, its past accuracy, and when the price becomes final |
| Price alert | A condition the user set | Your backend, by push notification | When the condition was met, and the price source |
| Portfolio | Holdings the user typed in | The user | That the holdings are the user's own entries, and the valuation time |
| Calendar | Dividends and disclosures | [official source or vendor] | The source and its publication time |
When you do not need us
If your idea can be tested with a spreadsheet, a simple website or a no-code tool, test it there first: an iPhone app is an expensive way to find out whether anyone wants the numbers. If an existing app, your broker's included, already does what you need, use it.
A larger firm is the better fit if you need a licensed trading platform, a bank account, card or wallet product, or many people working at once. If you are not sure what to build, start smaller: project and product analysis covers feasibility, data and licensing questions in a written report, before any code is written.
Need one screen for your own accounts?
A read-only view of your own balances and software does not need an app. See trading dashboards. For prices and history behind a product, see market data pipelines.
Questions about fintech app development
What kinds of fintech app do you build?
The information side of finance: market data, analysis, screening, calendars and portfolio tracking from data users enter or from read-only sources. Apps that hold money or send orders usually need a license or a licensed partner, and that is settled first.
Is Fincode a fintech software development company with client references?
Fincode is a software company in Istanbul with no client projects to cite. Fiva is the one real example, and it is our own product. What you can check instead is Fiva itself, the sample document on this page and the answers to technical questions you ask us before you decide.
Can I try Fiva?
Fiva is in beta for iPhone through a TestFlight invitation, and the app is in Turkish only. Fiva Web, the browser version, is being prepared. The Fiva page has the details.
Can you build a stock trading app?
Not as a public platform placing orders for other people. That needs a licensed firm behind it, and Apple says such apps should be submitted by the financial institution performing the service. Software that sends orders on your own account is a different service: broker API integration.
Do you build payment or banking apps?
Holding money or moving payments needs a license or a licensed provider first, and Fiva has no such work to show. If you already have that provider and need screens on top of it, raise it in your brief and we will say in writing whether it fits.
Do you build for Android?
This page covers iOS and web, and Fiva's iPhone beta is the only build you can try today. If you need Android, raise it in your brief and we will say in writing whether it fits.
Can an AI assistant go in the app?
It can, with its limits decided first: what data it may read, what it may never answer and how users learn that its answers can be wrong. In Fiva, for example, the assistant gives no buy, sell or personalized recommendations.
Can I hire fintech app developers from you?
Fincode takes this work as a project with a written scope, milestones and a test report, not as staff placed in your team. If you need people to join your company, a hiring route suits you better.
Who owns the code?
The written contract for your project sets who owns the code. Tell us what you need in your brief, and we will answer before we quote.
How much does fintech app development cost?
It depends on data licenses, integrations, platforms and security work; our guide to fintech app development cost covers the drivers. You get a written proposal with work items, dates and cost before work starts. Fees depend on scope and effort, not on trading volume or results.
Read more
Have an app in mind?
Tell us what the app should show, who will use it, where they are, where the data comes from and your timeline. Fincode is a software company and does not provide investment advice, portfolio management or crypto asset services. Trades can lose money.