@emergetools/emerge-score

emerge-score

Enabling Lighthouse for mobile

emerge-score is a community-driven framework for quantifying mobile app quality through standardized metrics and evaluations.

🔍 Overview

emerge-score helps teams measure, track, and improve mobile app quality by providing:

• A crowdsourced collection of app quality indicators and metrics
• An open scoring algorithm that converts indicators into a single numerical score
• Cross-platform support for iOS and Android
• Data-driven insights based on ecosystem comparisons
• Open-source implementation for transparency and community contributions

Think Lighthouse for web performance, but specifically designed for mobile apps.

✨ Key Features

• Standardized Scoring: Generate a clear, comparable quality score for your mobile app
• Multi-section Analysis: Evaluate various aspects of your app including Performance, Size, Accessibility, Privacy/Security, and Best Practices
• Interactive CLI: Guided process for evaluating your app
• Visual Reports: Generate HTML reports with detailed breakdowns of your app's scores
• Cross-platform: Support for both iOS and Android applications

🚀 Quick Start

The easiest way to run emerge-score is via npx or pnpx:

# Check the version
npx @emergetools/emerge-score --version

# Start the scoring process
npx @emergetools/emerge-score score

The CLI will guide you through selecting a platform, choosing a rubric, and evaluating your app across different quality metrics.

📊 Understanding the Score

emerge-score evaluates your app through sections containing individual audits:

• Sections: Grouped aspects of app quality (e.g., Performance, Size) with weighted importance
• Audits: Individual measurements of specific quality attributes

Audit types:

• Metrics: Numeric values compared against ecosystem data (scored from 0-N points)
• Checks: Binary yes/no evaluations (scored as 0 or N points, typically N=1)

The final score is calculated by:

1. Summing weighted audit points within each section
2. Combining weighted section scores into a raw total
3. Normalizing to a 0-100 integer score

Example output: HTML Report | JSON Data

📚 Documentation

CLI Commands

# View available commands
npx @emergetools/emerge-score --help

# Score your app
npx @emergetools/emerge-score score

# Generate a report from existing results
npx @emergetools/emerge-score report --input=results.json --output=report.html

# View the current scoring rubric
npx @emergetools/emerge-score rubric

Programmatic Usage

emerge-score can also be used as a TypeScript library:

import { computeAlgorithm, ALGORITHM } from "@emergetools/emerge-score";

// Your audit results
const results = {
  metricA: 100,
  checkB: true,
  // ...
};

// Platform context
const context = { platform: "ios" };

// Calculate score
const score = computeAlgorithm(ALGORITHM, results, context);
console.log(`Your app score: ${score.total}`);

🛠️ Development

Setup

# Clone the repository
git clone https://github.com/emergeTools/emerge-score
cd emerge-score

# Install dependencies
pnpm install --frozen-lockfile

# Build the project
./tools/build

Common Commands

# Run tests
./tools/test

# Format code
./tools/fix

# Run all pre-submit checks
./tools/presubmit

# Use the latest main branch build
npx @emergetools/emerge-score@next

🤝 Contributing

We welcome contributions from the community! See CONTRIBUTING.md for detailed guidelines.

Areas where you can help:

• Adding new audits and metrics
• Improving documentation
• Enhancing UI/reporting
• Fixing bugs
• Adding tests

📖 Terminology

Term	Description
Algorithm	The overall scoring system definition
Section	A category of related audits (e.g., Performance)
Audit	An individual quality measurement
Metric	A numeric measurement compared to ecosystem data
Check	A binary (yes/no) verification
Result	The outcome of a single audit
Results	Collection of all audit results
Context	Platform and environment information

🔗 Resources

• Launch Blog Post
• Flashlight
• Android App Performance Score

📄 License

MIT License - see LICENSE for details.