React Native development for a financial companion platform
Touchlane assembled a React Native team for a fintech startup that created a daily financial companion for millennials. The product aggregates cashback offers from over 200 retailers, rounds up debit card purchases into savings pots, and supports micro-investments for a tech-savvy audience.
- Staff Augmentation Service
- 2025
- Industry: FinTech
Initial Task
Description
The client needed a functional iOS and Android MVP within five months for a Series A pitch. The company chose React Native for speed and quality, but lacked in-house expertise. Touchlane integrated a dedicated team of two senior React Native developers into the client’s product squad. The developers adopted the Agile workflow and collaborated with the product manager (PM), helping design the core features and deliver the app on time.
The mandate was to build an MVP from Figma designs with three core features:
- secure linking of user bank accounts for transaction data
- a live feed of personalized cashback offers
- a visual ‘savings pot’ tracker for round-ups.
The app had to feel fast and responsive during shopping moments. All financial data aggregation and security were to be handled through established third-party providers, with no direct banking infrastructure built by the team.
Technology stack
Challenges
Technical challenges
1/ Managing the ‘hand-off’ between the native WebView sessions and the React Native application state. Data synchronization after a user linked an account had to be immediate to build trust.
2/ Designing a data layer that could support real-time updates to cashback offers without draining device battery or requiring constant manual refresh.
3/ Complex, interactive animations for the savings pots, which had to perform smoothly on mid-range Android devices.
Strict data security protocols
No sensitive financial data could be logged or stored in an unencrypted format, which required disciplined development practices. This meant the following:
1/ Our developers had to configure all third-party integrations to transmit data only through encrypted channels.
2/ The team needed to build dedicated secure audit trails for troubleshooting.
3/ Every data storage decision required review for encryption compliance.
4/ The production release needed a full security audit before distribution.
Process
Phase / 01.
Architecture and secure core
The Touchlane team established the application’s data flow and secure credential storage with React Native Keychain. The developers built the initial integration with the product’s SDK and handled the return of a public token to the backend.
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They also constructed the foundational navigation structure (React Navigation) and set up the modular state management for:
1/ User profile management – to handle user data and preferences
2/ Linked accounts and authentication – to manage connection status and session tokens
3/ Cashback offers and savings tracking – to store available offers and display the current state of all savings pots.
Phase / 02.
Feature implementation
Our team created the offer feed via implementing a cache-first strategy with React Query. The savings pot feature received particular attention, as designers provided complex Lottie animation files for pot-filling states, which our team integrated and tied to real-time balance updates.
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Moreover, we wrote a custom native module to handle precise haptic feedback for interactions like dragging coins into a pot. For the entire UI, our team used a shared component library to guarantee visual consistency.
Phase / 03.
Performance optimization and release
In the final six weeks, the focus shifted to performance. Touchlane’s team used React Native’s Performance Monitor and Flipper to identify and eliminate UI thread jank, especially on the interactive savings dashboard.
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We wrote over 300 unit tests and 40 end-to-end flows with the Detox testing framework to simulate everything, from bank linking failures to offer redemption. The app passed our client’s internal security audit before release.
Overall Result
The joint team delivered the MVP to the App Store and Google Play in 17 weeks. Touchlane’s senior engineers built core features, including the savings pot. Overall, our rich expertise in React Native helped in speeding up the development process and avoiding any rework. In addition, our engineers were able to join the project immediately and contribute from day one.
Within one month of launch, the product amassed 15,000 registered users. These users particularly enjoyed the roundup feature and noted it for its satisfying visual and haptic feedback. It showed a 22% higher weekly interaction rate than other app sections.
The client secured the next round of funding eight weeks after the launch. Investors said the existence of a polished, live mobile application was central to their decision. Touchlane continues to provide developer support for the client’s bi-weekly feature release cycle.
