SetGo is an interval timer application designed for gym and home workouts. Its primary function is to count sets, rest periods, and rounds, using color-coded phases to indicate status: orange for getting ready, green for work intervals, and blue for rest. The app is free, works offline, and does not require an account. It is available for iPhone, iPad, and through a web browser, and it does not collect, store, or transmit personal data. The app allows users to build workout plans directly in a browser-based builder, then run them on the web or download them as JSON files for use in the app. Each plan file contains the workout name, exercises, and the sets, work seconds, and rest seconds for each exercise. Users can also export workouts from the app and upload them into the builder for editing. Published plans can be rated and reviewed by other users, with the highest-rated plans appearing at the top of the list. Key features include voice, beep, and vibration announcements, a 3-2-1 countdown, and a quick timer accessible in three taps. The app supports multiple rounds, rest between exercises, and individual sets, work, and rest durations for every exercise. It includes ten built-in plans, each with three difficulty levels. Typical use cases involve following a structured workout routine, creating custom training plans, and sharing those plans with others. The workflow generally involves listing exercises with their parameters, starting the timer and following the visual and audio cues, and optionally sharing or publishing the plan for community use.