Glosso Studio

Glosso Studio is an offline-first pronunciation training application built with Kotlin Multiplatform and Jetpack Compose. It provides real-time phonetic assessment and a structured curriculum to help users improve their spoken English.

Features

Phonetic Assessment

The application uses the Allosaurus model (specifically eng2102) to perform phonetic recognition. It processes 8kHz audio, computes Mel-frequency cepstral coefficients (MFCCs), and runs inference via ONNX Runtime to provide feedback on pronunciation accuracy.

Offline-First Architecture

The application is designed to be fully functional offline once the initial assets are retrieved.

• ONNX Runtime: Executes the acoustic model (eng2102) directly on the device.
• Dynamic Database Download: To keep the APK size minimal, curriculum databases are downloaded on-demand from GitLab when a level is first accessed.
• Room Database: Manages the repository of practice sentences and user progress.
• Git LFS: Used for managing large binary assets in the repository.

Mastery and Progress Tracking

• Curriculum Levels: Six difficulty tiers ranging from Beginner to Mastery.
• Mastery System: Sentences are marked as mastered when users achieve a threshold score (85%+).
• Streak Tracking: Encourages consistent practice through a daily streak system verified against activity logs.
• Statistics: Comprehensive tracking of total mastered phrases and level-specific progress.

Tech Stack

• Framework: Kotlin Multiplatform (KMP)
• UI: Jetpack Compose (Android)
• Dependency Injection: Koin
• Database: Room (Android)
• Networking: Ktor Client
• Machine Learning: ONNX Runtime for Android
• Phonetic Model: Allosaurus eng2102 (GPL-3.0) for high-accuracy phonetic recognition
• Text-to-Speech: Qwen3-TTS (Apache-2.0) for high-fidelity speech synthesis
• Audio Processing: Custom MFCC implementation for 8kHz signal processing
• Serialization: Kotlinx Serialization

Prerequisites

• Git LFS: Required to pull the large ONNX models and database.
• Android Studio: Hedgehog (2023.1.1) or later recommended.
• JDK: Version 17.

Setup and Installation

1. Install Git LFS Ensure Git LFS is installed on your system before cloning:

   git lfs install

2. Clone the Repository

   git clone git@gitlab.com:shirobyte421/glosso-studio.git
   cd glosso-studio
   git lfs pull

3. Open in Android Studio Open the root directory as a project. Android Studio will automatically start the Gradle sync process and download necessary dependencies.

4. Run the Application Select the androidApp configuration and run it on a physical device or emulator (API 26 or higher).

Architecture Overview

The project follows a clean architecture pattern within the Kotlin Multiplatform structure:

• shared module: Contains the domain logic, repositories, and cross-platform use cases.
• androidApp module: Contains the Compose UI, Android-specific data implementations (Room, Audio), and the ONNX integration.

License

This project is licensed under the GNU Affero General Public License v3 (AGPLv3). See the LICENSE file for the full license text.

F-Droid

Glosso Studio is designed to be compatible with F-Droid.

• Metadata: Located in fastlane/metadata/android.
• Build Recipe: The me.shirobyte42.glosso.yml file is provided as a reference for F-Droid inclusion.