Creating an International Power Bank Sharing Ecosystem for Mr. Charge
Mr. Charge is a power bank sharing service that allows users to pick up a charger at one station and then return it to any other station within the network. The network focuses on high-traffic locations such as shopping centers, airports, train stations, and cafés. The client approached us with the task of creating a product from scratch.
12 months
Active phase and launch
Task: Seamless Rental Service
The client requested us to develop a convenient and reliable mobile app for interacting with the network of charging stations.
Key business requirements:
- Cross-platform: Full coverage of iOS and Android audiences.
- Hardware interaction stability: Flawless communication between the app and rental stations (slots, errors, charge status, etc.).
- Marketing flexibility: Implementation of a complex promo code system to attract and retain customers.
- Seamless UX: The user journey from station selection to payment needed to be as short and straightforward as possible.
Solution
We developed both platforms natively and combined them with a powerful backend built on Laravel.
- Technology stack: Focus on reliability
- Android (Native): We used the MVVM architecture, Hilt for dependency injection, and Cicerone for navigation. This resulted in clean architecture and high performance.
- iOS (Native): Native development in Swift to ensure the best user experience and smooth interface on Apple devices.
- Backend (Laravel + SQL): Chosen as a proven and flexible platform for building complex business logic, capable of serving both apps through a single API.
- Technical challenge: Support for the Huawei ecosystem
- One of the strategic objectives was to cover the entire Android device market, including those that do not support Google services.
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- Issue: The app needed to be published not only on Google Play but also in Huawei AppGallery, which uses other services (maps, push notifications, analytics, etc.).
- Solution: We set up support for two separate versions (builds) of the app. A complex CI/CD system was organized for parallel testing and publishing in two different ecosystems.
- Integration with equipment
- The most critical part of the project was connecting the software to physical stations.
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- Challenge: Connecting the supplier's stations (Relink) required working with non-standard communication protocols.
- Solution: We implemented real-time data synchronization. The system instantly updates station statuses (such as available slots and errors) and processes rental/return events, providing users with an up-to-date map of the city.
- Marketing tools
- To grow their business, the client needed more than just a “discount”—they required a flexible promotion builder.
- Implementation: We created a scalable promo code system on the backend that supports various types of discounts, application rules, and restrictions. We also configured ad data consolidation from station screens for reporting purposes.
Development Process
We followed the entire product development cycle, from requirements analysis and prototyping to launch and support.
Testing
This process was conducted in stages, starting with internal alpha testing, followed by a closed beta for a limited group, and finally releasing to production. This allowed us to catch UX bugs before they could impact regular users.
Teamwork
A dedicated cross-functional team of eight specialists worked on the project, including a dedicated QA engineer and business analyst.
- Project Manager
- Team Lead
- Backend Developers (2)
- Android Developer
- iOS Developer
- QA Engineer
- Business Analyst
- UX/UI Designer
Technology Stack
Kotlin (Android)
Swift (iOS)
PHP (Backend)
Laravel (Backend)
Firebase
SQLResults
In 12 months, we created a functional and measurable cross-platform ecosystem that was ready for scaling.
- Numbers: Over 12,400 400 installations across all platforms.
- High conversion: The app in the App Store achieved an outstanding install conversion rate of 59.8%.
- Geography: The product was successfully launched not only in its local market but also in Europe (Romania, UK, Italy, Cyprus, Slovenia).
- Engagement: The app has gained a base of active users (~3,800 per month on Android) with high usage frequency (4.54 sessions per device on iOS).
The customer received a product with proven demand in the international market, minimal technical debt, and an architecture ready for new integrations, which became a compelling argument for investor negotiations.
