Nod: Sleep Debt Tracker

Nod is a dedicated productivity and lifestyle utility designed to help users track their sleep patterns, calculate accumulated "Sleep Debt," and optimize their daily recovery.

Core Purpose
Nod helps you visualize the relationship between your actual sleep duration and your biological sleep needs. By logging your nightly sleep, you can maintain a clear, quantifiable record of your sleep health. The app is designed for users who want to understand how inconsistent sleep schedules contribute to fatigue and who seek a structured, data-driven approach to recovery.

Key Features

Sleep Debt Calculation: Nod calculates a rolling 14-night window of sleep data. It compares your nightly sleep duration against your customized sleep need baseline to determine your net "Sleep Debt" in hours and minutes.

Sleep Logging: A simplified interface for recording daily bedtime and wake-up times. The app uses this historical data to automatically calculate your sleep duration.

Bedtime Recommendations: Based on your wake-up goal and current sleep debt, Nod provides intelligent bedtime recommendations to help you align your schedule with your body's needs.

Recovery Insights: The app provides structured feedback on your sleep trends, helping you identify if your sleep debt is increasing or decreasing over a 7-day period.

Privacy-First Architecture: Nod operates entirely offline. There are no user accounts, no cloud sync, and no third-party analytics trackers. All data is stored locally on the device, ensuring user data privacy.

Nod Pro (Optional Premium Features)
Nod offers a one-time, lifetime purchase for users who require advanced insights:

30-Day Sleep Trends: Visualize your sleep health over an extended 30-day period.

Personalized Recovery Plan: Receive a tailored, algorithmic plan that breaks down exactly how many minutes you should sleep earlier over a specific number of nights to reduce your sleep debt to zero safely.