インターバルはシンプルで使いやすいです。広告なしのプロバージョン。
An interval timer for training and workouts or work and rest times. Interval is simple and easy to use. An awesome timer, whether you're working on cycling, running, lifting weights, exercise, workout, stretching, or boxing.
Suitable for all kinds of activities, including Boxing round timer, Circuit training, HIIT training, etc.