WorkoutStack is a gym workout tracking and logging application designed for iOS. Its primary function is to allow users to record their sets quickly during a workout, while also providing tools to monitor long-term strength progress and muscle training volume. The app is built around a focused, distraction-free logging experience, with bold, color-coded exercises that collapse into a clean view as they are completed. Key features include a 1RM (one-rep max) calculator and a library of over 2,900 exercises, each accompanied by posture videos to demonstrate proper form. Users can build a custom statistics dashboard to analyze their performance over time. The app does not require an account to use and operates fully offline, making it accessible without an internet connection. A privacy policy is available, and the app is free to download from the App Store. Typical use cases involve individuals logging their gym workouts set by set, tracking their lifts for progression, and reviewing which muscle groups have been trained. The workflow centers on quickly entering sets as they are completed, with the interface designed to minimize disruption during training. The exercise library helps users find and learn new movements, while the dashboard provides data for self-assessment. WorkoutStack is available exclusively on iOS and is intended for those who want a simple, direct logging tool without the need for account registration or constant connectivity.