High Intensity Interval Training, or HIIT for short, has quickly become many fitness enthusiasts' go-to for efficient, effective workouts. But since HIIT requires switching between high and low intervals at set times, repeatedly, one has to watch a clock, watch or basic timer to know when to start, switch and end. HIIT Timer helps with this by playing a notifier sound to indicate the start, switching and end of a HIIT workout. No need to watch anything! Just set your parameters, start it and then listen for the notifier sounds(make sure your phone isn't muted)! This allows you to focus on what you're doing for your workout instead of constantly checking a clock or watch.