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. In the Gulf that usually starts at the front door, with eKYC and remote onboarding built to the CBUAE guidance. 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 — in India, that means a V-CIP video KYC flow built to the RBI Master Direction — 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. The reasoning is in core banking integration: what actually connects to what.
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 set out why in how to build a mobile banking app.
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