ONLINEPAY WALLET
We developed native iOS and Android apps for OnlinePay wallet, providing a secure way to manage finances on the go.
Categories:
Web AppMobile AppiOS AppAndroid AppFintechProject site: onlinepay.com
OnlinePay Wallet highlights our expertise in developing secure, high-performance native mobile applications for the Fintech sector. Vasilkoff Ltd specialised in creating platform-specific solutions (iOS and Android) that provide users with a seamless and convenient way to manage finances. This experience is ideal for businesses needing secure financial management tools and tailored mobile apps, ensuring enhanced user experience and robust security protocols for on-the-go financial management.

In the enterprise world of financial technology, success depends on precision, trust, and the ability to scale. At Vasilkoff Ltd, we have repeatedly proven that we can take on projects where mistakes are simply not allowed. One of the most ambitious cases in our portfolio is the development of a secure and high-performance fintech wallet app — designed for both iOS and Android — for a major online payments company.
This case study is not a theoretical guide, but a direct account of how our team approached a challenge that demanded flawless execution across mobile, backend, and compliance domains.
The Challenge: Enterprise-Grade Requirements
The client, a major fintech operator handling high transaction volumes across multiple jurisdictions, came to us with an urgent requirement:
to build a mobile wallet app that could serve millions of users, process real-time payments, and comply with strict financial regulations.
Key requirements included:
- Cross-platform mobile apps (iOS and Android) with a unified experience.
- Bank-grade security with biometric login, PIN fallback, and encrypted local storage.
- Scalable backend architecture that could handle thousands of concurrent transactions.
- Integration with existing payment rails and card processors.
- Compliance features: KYC, AML monitoring hooks, audit logging.
- Maintainability through modular architecture and automated CI/CD pipelines.
For enterprises, it is not only about features — it is about governance, scalability, and the ability to grow without breaking.
Our Approach: Structured and Scalable
From day one, we treated this as an enterprise engagement, not a startup-style MVP.
That meant formal requirement gathering, architectural modeling, and phased delivery.
1. Outstaffing and Dedicated Team
We provided a dedicated outstaffing team:
- Mobile engineers specialized in Swift (iOS) and Kotlin (Android).
- Backend engineers on Node.js + PostgreSQL, with Kubernetes orchestration for scalability.
- QA automation specialists with a compliance-first test matrix.
- A project manager with fintech background to align delivery with regulatory expectations.
This model ensured transparency, cost efficiency, and focus — the client could monitor progress while we retained delivery responsibility.
2. Architecture Design
We opted for a microservice-oriented backend, containerized with Docker, deployed under Kubernetes clusters.
API endpoints were secured with OAuth2.0 + JWT, and all traffic was end-to-end encrypted.
The mobile apps were built natively, to guarantee performance and security. Flutter or hybrid frameworks were rejected due to risk factors for banking UX.
3. Compliance Integration
We integrated:
- KYC verification APIs to onboard users with document checks.
- AML pattern detection hooks connected to the client’s compliance systems.
- Regulatory logging pipelines so every transaction is auditable.
Our role was not only technical — it was about aligning development with legal frameworks across multiple countries.
Results Delivered
After a 10-month development cycle, the app was released to closed beta, then scaled into public release. The results:
- iOS and Android apps live in production, with a unified brand experience.
- Transaction volumes scaled successfully: thousands of concurrent payments with sub-second confirmation times.
- Zero compliance breaches since launch — the system aligned with regulators from day one.
- Infrastructure cost optimization with autoscaling and containerized workloads.
- User satisfaction with seamless biometric login and intuitive wallet flows.
This project proved that enterprise fintech apps can be both secure and user-friendly when executed with the right partner.
Lessons for Enterprise Partners
From this project, several insights are relevant for any CTO or enterprise manager considering a similar build:
- Native apps are still the gold standard for fintech. Performance and security outweigh the convenience of cross-platform shortcuts.
- Outstaffing gives control without overhead. The client retained visibility, while we shouldered the complexity of hiring, coordination, and delivery.
- Compliance must be built in, not bolted on. Apps in regulated industries fail when compliance is treated as an afterthought.
- Architecture decisions pay dividends. Containerization and microservices allowed fast scaling during peak transaction seasons.
Why Enterprises Choose Vasilkoff Ltd
We know what enterprises expect when outsourcing high-stakes projects:
- Confidentiality and strict NDAs.
- Proven delivery methodology, not experiments.
- Experience in regulated industries (finance, telecom, VPN infrastructure).
- Transparent reporting with agile sprints and milestone tracking.
This is why Vasilkoff Ltd is trusted not just for startups, but also for established corporations needing reliable fintech solutions.
Work With Us
If your company is exploring the next stage of fintech innovation — whether it is a wallet, neobank platform, or payment infrastructure — you don’t need to gamble on delivery.
Vasilkoff Ltd provides skilled outstaffing and full-cycle development to execute projects where security, scalability, and compliance are non-negotiable.
Contact us today to discuss how we can support your enterprise initiative.