GoDeeper | Building an Offline-First Neurofeedback App That Listens to Your Brain

Founders in the neurotech space face a unique mix of hurdles:

• Combining hardware and software into one seamless UX.
• Building around unstable third-party devices (like EEG headbands).
• Translating scientific logic into smooth mobile app flows.
• Balancing innovation with reliability.

GoDeeper had a vision: democratize access to advanced neurofeedback through a sleek mobile experience. But building that meant solving challenges that stretched from Bluetooth instability to signal processing in C++.

The journey started in 2021. Milo was originally brought on just to build a small admin panel. But as our collaboration deepened, so did our responsibilities. By early 2022, we were leading full-stack development across mobile, web, and backend.

The product now consists of:

• A mobile app (iOS + Android) built in React Native, with C++ Turbo Modules for real-time EEG signal processing.
• A Coach Panel in React for reviewing session data.
• A WordPress website for onboarding experienced meditators.

GoDeeper allows users to:

• Connect their Muse EEG headband.
• Run real-time meditation sessions with audio/visual feedback.
• Track brainwave activity (alpha, beta, theta, delta, gamma).
• Analyze sessions after the fact.
• Collaborate with certified meditation coaches.

One of the core innovations is local signal processing. Originally, EEG data was streamed to the cloud. But connection issues and latency made the experience unreliable. Our team proposed and built a fully local solution using C++ modules, enabling true offline functionality.

As one stakeholder said after using the new version:

I wish I had trusted Milo with this part a year earlier.

This wasn’t a straight line. A few of the major hurdles we faced:

1. Flutter didn’t cut it. The original codebase used Flutter, but it struggled with Bluetooth performance and hardware stability. We migrated the native layer to React Native for better support and long-term maintainability.

2. Complex EEG signal processing. The original processing happened in a microservice written in C, hosted in the cloud. We rebuilt this as a local module in C++ using React Native’s Turbo Modules, maintaining performance while gaining stability and privacy.

3. UI/UX pivot after external audit. An expert UX audit reshaped the app’s flow, leading us to redesign large parts of the UI based on real user feedback.

4. QA transformation. Our QA team introduced full automation (Pytest, Playwright, Locust), test coverage, CI/CD pipelines, and AI-powered reporting. This improved deployment speed and product reliability.

5. Winning trust for full ownership. Initially, the client was hesitant to let us touch core EEG components. But after consistent delivery and technical depth, they gave us full control of the product roadmap.

The technology behind GoDeeper combines multiple layers:

• React Native for cross-platform mobile performance
• React WebView for UI flexibility
• Turbo Modules in C++ to process EEG signals in real time on-device
• BLE (Bluetooth Low Energy) for reliable connection with Muse headbands

We designed a custom bridge between the native and web layers to ensure fast data transmission without sacrificing modularity. Turbo Modules gave us the performance edge we needed to handle dense EEG signal streams in real time.

On the QA side, we implemented a robust test framework with:

• Unit, UI, API, and performance testing
• Mocked network conditions
• Self-healing tests supported by AI
• TestRail integration and automated release checklists

And for the cloud handover - we created a seamless fallback system: the app now works entirely offline and syncs back to the cloud once a connection is re-established.

Here’s how the app works from a user perspective:

Onboarding & Personalization

Users create a profile, define their goals, and generate a personal EEG baseline through an initial session.

Practice Selection & Calibration

They select meditation styles from a practice library and calibrate them based on their brainwave patterns.

Live Sessions

The app reads EEG data in real time, gives subtle audio or visual feedback, and monitors attention, breath, and brainwave states.

Post-Session Analysis

Users receive detailed insights: score, focus loss events, EEG trends, and coaching suggestions.

BrainWave Analyzer

Advanced users and researchers can view raw EEG data by channel and time to assess meditative depth and consistency.

Coach Panel

Certified coaches can monitor users' data, suggest practices, and guide them with personalized recommendations.

Here are three takeaways from GoDeeper’s journey:

Start small, earn trust. Taking ownership didn’t happen overnight. We began with a backend tool and grew our role through consistent delivery.

Offline-first isn’t just a feature—it’s a mindset. Building for real-world conditions (poor internet, mobile constraints) made the product more reliable and scalable.

Scientific doesn’t mean slow. With the right architecture, even advanced research-grade tools can feel smooth and user-friendly.

GoDeeper is a perfect example of what we love doing: building serious, meaningful technology that supports human growth. We didn’t just write code—we shaped the architecture, solved the signal chain, stabilized the product, and contributed to a vision bigger than the app itself.

This is what happens when a founder brings a bold idea, and a tech partner knows how to guide it to life.

With the offline-first infrastructure now solid, the next evolution of GoDeeper will include:

• AI-driven meditation coaches to help users pick the right practice based on data.
• Sprint automation agents to reduce overhead in the dev process.
• Increased integration of HRV and breathing data for full-spectrum biofeedback.
• Open research initiatives contributing EEG data to neuroscience and mindfulness studies.

Milo continues to support this roadmap, combining technical execution with strategic input.

From patchy cloud connections to fully offline C++ signal processing, the GoDeeper app evolved into a robust neurofeedback platform designed for real-life use. It supports meditative growth, scientific research, and user wellbeing—all in one unified system.

If you're building something that sits at the edge of hardware, AI, or human development, Milo can help you turn the chaos into clarity.

👉 Let’s talk about building your vision—start to finish.