Great app to train HIIT with HR zones control
Old-school UI/UX but the ONLY app I know so far which allow to have both at one screen: - intervals visualization - HR zone visualization Great approach to announce intervals and HR zones change. Nice 3 sec count down before any new interval. Flexible workout/intervals builder which covers all possible cases. Reasonable price. Highly recommended if you have elliptical machine or treadmill and want to make scientifically-based training using your HR zones.