I had an idea to build an app that can help runners better pace themselves consistently. The app's function is to let the user pick an interval of seconds and then a timer will start. Let's say the user picks 30s intervals, then every 30s the Apple Watch will vibrate and the timer will reset back to 0. The goal is for when runners are trying to achieve consistent paces, such as 60s per 400m lap, the watch can vibrate every 60s and they can get a notion for whether or not they are on pace to run their final race time goal!