Focus Track - macOS App & Window Focus Monitor

A production-ready Rust CLI application for tracking application and window focus changes on macOS. Monitors app switches, window changes, and browser tab changes with millisecond precision.

Features

• Real-time app tracking - Monitors active application changes
• Window title tracking - Captures window titles for all applications
• Browser tab support - Special handling for Chrome, Safari, and Firefox tabs
• Multiple output formats - Text or JSON output for easy integration
• Low resource usage - Efficient polling with configurable intervals
• Privacy-focused - Runs locally, no data leaves your machine

Installation

From Source

# Clone the repository
git clone https://github.com/yourusername/rust_clipboard_monitor_cli.git
cd rust_clipboard_monitor_cli

# Build release version
cargo build --release

# Run the binary
./target/release/rust_clipboard_monitor_cli

Usage

Basic Usage

# Start tracking with default settings (text output, 250ms polling)
./rust_clipboard_monitor_cli

# Use JSON output for programmatic consumption
./rust_clipboard_monitor_cli --format json

# Increase polling frequency for more responsive tracking
./rust_clipboard_monitor_cli --poll-interval 100

# Enable verbose logging
./rust_clipboard_monitor_cli -v  # Info level
./rust_clipboard_monitor_cli -vv # Debug level

Command Line Options

Options:
  -f, --format <FORMAT>                Output format: text or json [default: text]
  -v, --verbose...                     Verbosity level (-v for info, -vv for debug)
      --no-prompt                      Don't prompt for accessibility permissions
      --poll-interval <POLL_INTERVAL>  Poll interval in milliseconds [default: 250]
  -h, --help                           Print help
  -V, --version                        Print version

Output Examples

Text Format

Started tracking: Cursor (com.todesktop.230313mzl4w4u92)
  Window/Tab: main.rs — rust_clipboard_monitor_cli
App switch: Cursor → Google Chrome (spent 45.2s)
  Window/Tab: GitHub - rust-lang/rust
Window change in Google Chrome: "GitHub - rust-lang/rust" → "Stack Overflow" (spent 12.3s)

JSON Format

{"event_type":"start","app":{"app_name":"Cursor","bundle_id":"com.todesktop.230313mzl4w4u92","window_title":"main.rs"}}
{"event_type":"app_switch","from":{"app_name":"Cursor","bundle_id":"com.todesktop.230313mzl4w4u92","window_title":"main.rs"},"to":{"app_name":"Google Chrome","bundle_id":"com.google.Chrome","window_title":"GitHub"},"duration_ms":45234}

Permissions

The application works best with accessibility permissions but can function without them:

With Accessibility Permissions

• Full window title tracking
• Browser tab title tracking
• All application window information

Without Accessibility Permissions

• Basic app switching detection
• Bundle ID and app name tracking
• Limited window information

To grant permissions:

1. Open System Settings → Privacy & Security → Accessibility
2. Add the application to the list
3. Enable the checkbox

Architecture

The application uses a hybrid approach for maximum compatibility:

• AppleScript for reliable app and window information
• Polling-based monitoring for consistent tracking
• Browser-specific handling for tab titles
• Efficient state management to detect changes

Performance

• Memory usage: ~5-10MB
• CPU usage: <1% with default polling interval
• Polling interval: Configurable (50ms - 5000ms)

Privacy & Security

• All processing happens locally
• No network connections
• No data storage (output only)
• Open source for full transparency

Use Cases

• Productivity tracking - Monitor time spent in different applications
• Development workflows - Track context switches during coding
• Research - Analyze application usage patterns
• Automation - Trigger actions based on app switches
• Time tracking - Accurate work time allocation

Building from Source

Requirements

• Rust 1.70 or later
• macOS 11.0 or later
• Xcode Command Line Tools

Development

# Run in development mode
cargo run

# Run with verbose output
RUST_LOG=debug cargo run

# Run tests
cargo test

# Build optimized binary
cargo build --release

Integration Examples

With Shell Scripts

#!/bin/bash
# Log app usage to file
./rust_clipboard_monitor_cli --format json >> ~/app_usage.jsonl

With Python

import subprocess
import json

proc = subprocess.Popen(
    ['./rust_clipboard_monitor_cli', '--format', 'json'],
    stdout=subprocess.PIPE,
    text=True
)

for line in proc.stdout:
    event = json.loads(line)
    print(f"Event: {event['event_type']}")

Troubleshooting

Application not detecting window changes

• Grant accessibility permissions in System Settings
• Some applications may not expose window information

High CPU usage

• Increase the poll interval: --poll-interval 500
• Check for other monitoring applications

Permission prompt not appearing

• Run without --no-prompt flag
• Manually add in System Settings → Privacy & Security → Accessibility

Contributing

Contributions are welcome! Please feel free to submit pull requests or open issues.

License

MIT License - See LICENSE file for details

Acknowledgments

Built with:

• clap - Command line argument parsing
• serde - Serialization framework
• tracing - Application instrumentation

Roadmap

• Event-driven monitoring using macOS notifications
• Support for multiple monitors/spaces
• Window position and size tracking
• Export to various time tracking formats
• Configuration file support
• Historical data analysis