Greenely - Save energy

Mobile energy management

Greenely is a Swedish energy-tech app that gives users full control over their electricity consumption and costs. The app provides real-time spot price tracking, smart device integrations, and detailed consumption analytics to help households reduce energy costs and optimize usage. Available in Sweden and Finland, Greenely combines a digital electricity contract with smart home automation, allowing users to connect EV chargers, solar panels, batteries, heating systems, and real-time smart meters—all managed through a single app. Key features include hourly and 15-minute spot price monitoring, smart charging for electric vehicles, automated heating optimization, real-time consumption tracking via SaveEye smart meters, and grid-balancing rewards for connected devices. The app serves 100,000+ users with 100% fossil-free energy.

Location

Cluj-Napoca

Feb 2025 - Present

Industry

Energy

Downloads

100.000+

Rating

4.2⭐️

Play Store

Challenge

The existing Android app was built on legacy architecture with XML layouts,

fragmented codebases, and tightly coupled components. Key challenges included:

• Outdated UI layer: XML-based views with complex fragment navigation made

feature development slow and error-prone.

• Scalability issues: Monolithic architecture lacked clear separation between

data, domain, and presentation layers, making testing and maintenance difficult.

• Multi-market expansion: Supporting Finland required extensive localization,

currency handling (SEK/EUR), and market-specific feature flags without

duplicating code.

• IoT complexity: Integrating diverse smart devices (EV chargers, batteries,

solar panels, heating systems, weather stations) required real-time WebSocket

connections and device-specific UI states.

• Hardware provisioning: SaveEye smart meter onboarding required complex

Bluetooth LE scanning, WiFi configuration, and real-time data synchronization

with robust error recovery.

• Performance issues: Dashboard loading times were slow, with visible flickering,

race conditions, and stability issues affecting user experience.

• Code quality gaps: No consistent linting, limited test coverage, and manual

deployment processes slowed down the development cycle.

Results

• Dashboard 2.0 delivered: Complete migration from XML to Jetpack Compose with Clean Architecture, reducing load times and improving code maintainability.

• Finland market launched: Multi-language support, currency adaptations, and feature flags enabled seamless expansion to a new market.

• 6+ smart device integrations: EV chargers (ChargeBox, Zaptec), solar panels, batteries (Pixii, Emulate), heating systems (MyUplink), and weather stations connected with real-time monitoring.

• SaveEye onboarding completed: End-to-end Bluetooth LE and WiFi provisioning with QR code pairing, automatic retries, and real-time data sync.

• Real-time spot price charts: Interactive Vico 2.1.3 charts with 15-minute intervals, landscape mode, and persistent marker states for energy analysis.

• App stability improved: Baseline profiles, Compose optimizations, and crash fixes via Crashlytics reduced critical issues and improved performance.

• Modular architecture established: Feature modules (dashboard, facility, solar-panel-details, saveeye-onboarding) with clear layer separation (public, ui, impl-wire).

• Code quality standards: ktlint, git hooks, and automated code review processes implemented across the codebase.

• CI/CD enhanced: Bitrise pipeline with Firebase App Distribution, GitHub Packages migration, and Kotlin 2.1.10 with K2 compiler upgrade.

• Analytics integrated: Mixpanel, Firebase Analytics, AppsFlyer, and Intercom for comprehensive user journey tracking and product insights.

Stack

Conclusion

The Greenely Android app transformation delivered a modern, scalable, and maintainable codebase that supports rapid feature development and multi-market growth. By migrating to Jetpack Compose with Clean Architecture, the app now offers faster load times, smoother UI interactions, and a solid foundation for future smart home integrations.

The modular architecture enables independent feature development while maintaining code quality through automated linting and testing. Real-time IoT connectivity through WebSockets and Bluetooth LE provisioning positions Greenely as a leader in the smart energy management space.

With 100,000+ downloads and a 4.6-star rating, the app successfully serves users across Sweden and Finland, helping them optimize energy consumption, reduce costs, and contribute to a more sustainable energy grid.

Tech Stack: Kotlin, Jetpack Compose, Hilt, Coroutines, Flows, WebSockets, Room, DataStore, Firebase, Bitrise, Mixpanel, AppsFlyer, Intercom, Vico Charts, Bluetooth LE