Fintech & banking
Fintech app development — secure mobile banking on your existing core.
Appsarmy is a fintech app development company. We build mobile banking, wallet, and lending apps that integrate with the core banking system you already run — to the security and compliance bar of a real financial institution. It is the intersection of our two strongest crafts: mobile app development and AI.
Fintech software development, built to a bank's bar.
Banking apps fail on the parts users never see: the auth, the integration, and the audit. Our fintech app development work covers all three — the customer-facing app, the secure layer beneath it, and the connection into a core that predates it by decades. New to this? Start with our guide, how to build a fintech app.
Mobile banking app development
Digital banking app development in Flutter for iOS and Android — accounts, transfers, statements, cards, and servicing, in a single codebase that still passes an enterprise security audit. Multi-language and multi-region where the rollout demands it.
Our mobile craftCore banking integration
A secure API layer in front of the system of record — authentication, encryption, tokenisation, and protocol translation down to legacy interfaces. The core stays exactly where it is; the customer experience stops being held hostage by it.
No rip-and-replaceWallets & payment apps
Digital wallet and payment app development — P2P, merchant payments, card issuing, and gateway integration.
Lending & neobank apps
Onboarding, credit decisioning, disbursement, and collections — a digital-first bank or lender, end to end.
Secure authentication
Challenge-response login, biometric MFA, OTP, and per-transaction signing — the layer regulators actually read.
Modernize the app. Keep the core.
From a retail banking app to a neobank.
Retail mobile banking
Accounts, transfers, cards, statements, and servicing on top of an existing core — the pattern behind our work with a legacy back-office at a GCC retail bank, delivered in phases against a live rollout. On an Oracle core, that is custom OBDX mobile app development on Oracle Banking Digital Experience.
Digital wallets & payments
P2P and merchant payments, top-ups, card issuing and controls, and payment gateway integration — with tokenised card data, never raw PANs on the device.
Lending & BNPL
Digital onboarding with KYC, credit decisioning, disbursement, repayment, and collections — the full loan lifecycle, not just the application form.
Neobank platforms
A digital-first bank built from the ledger up, or a BaaS-fronted product — onboarding, accounts, cards, and support in one app.
Corporate & SME banking
Multi-user mandates, maker-checker approvals, bulk payments, and entitlements — the workflows business banking actually runs on.
Open banking & PSD2 APIs
Account information and payment initiation endpoints with strong customer authentication and consent management, exposed safely to third parties.
Compliance is designed in, not audited on.
Scope & controls
A written SOW that maps each obligation — PCI DSS, PSD2, GDPR, AML — to a specific control in the build.
Threat model
Auth flows, key handling, and device trust designed before a screen. Where the money moves, so does the review.
Integration
The secure API layer onto the core, in a sandbox, proving the hardest call path works before feature work starts.
Build
Flutter delivery in short cycles, with a working build you can hold each sprint and an audit trail from day one.
Pen test
Independent penetration testing and remediation, plus store review and your own IT security sign-off.
Launch
Phased rollout with monitoring, fraud alerting, and a support line that does not start at the account manager.
The banking stack we build on.
Our strongest niche, not a vertical we added.
Banking-grade, proven
We have shipped a customer-facing app onto a bank's existing core, meeting its security bar and its rollout schedule. That is a different exercise from building a fintech demo.
We don't touch the core
The system of record stays where it is. We modernize in front of it, so the programme cannot be killed by a core migration nobody signed up for.
Mobile and AI in one team
The app and the fraud or anomaly model are built by the same people — the intersection of our mobile and AI practices, without a handoff.
NDA-first, senior-led
Strict IP protection, senior engineers on every call, and direct access — the way institutional clients in the US, UK, EU, and GCC expect to work.
Work with us the way that fits.
Integration discovery
A fixed engagement that proves the hardest call path onto your core works — before you fund an app.
Fixed-scope build
A defined app, written scope, clear price, with the compliance controls named in the SOW.
Dedicated banking pod
A senior Flutter and integration pod embedded with your team, sprint after sprint, through audit and rollout.
Fintech & banking questions.
What fintech app development services do you offer?
Mobile and digital banking apps, wallets and payment apps, lending and neobank platforms — plus the secure layer that integrates them with an existing core.
Can you integrate with our core banking system?
Yes, without replacing it. We build a secure API layer in front of the system of record, handling auth, encryption, tokenisation, and translation down to legacy interfaces.
How do you secure a mobile banking app?
Biometric MFA, challenge-response login, and per-transaction signing, with certificate pinning, tokenisation, end-to-end encryption, secure device storage, and full audit logging.
Which compliance standards do you build to?
PCI DSS, PSD2 with strong customer authentication, GDPR, and AML/KYC. Each obligation is mapped to a control in the SOW before the build, not retrofitted after an audit.
Do you build wallets and payment apps?
Yes — P2P and merchant payments, card issuing and controls, lending and BNPL flows, and payment gateway and open banking integrations.
How long does a banking app take?
It depends on integration and compliance load. A wallet or lending MVP is smaller; a full retail banking app on a legacy core, with pen testing and an audit cycle, is larger. We scope it in writing, phased against your rollout.
Let's build your banking app.
business days