Scatto: Zone 2 Running Coach

Scatto is a heart-rate running coach. You run in the range you chose — zone 2 is the starting point — and corrections come in your earphones only when you stay out of it long enough to be worth a cue. A short spike passes in silence. It works in two ways. With an Apple Watch, the coach runs on the watch itself. Open Scatto on your wrist, tap Start and run. A voice and a tap on the wrist let you know. The watch reads heart rate and distance. The watch GPS draws the route, which can be saved to the Health app. Without an Apple Watch, the iPhone listens to a Bluetooth heart-rate sensor: Garmin, Polar, Coros or a chest strap. Nothing is installed on the watch. On the Run screen, the step-by-step guide is written for Garmin: turn on heart-rate broadcast and start the activity on the watch. When Scatto finds the sensor, tap Start and the coach speaks in your earphones, over your music. If no heartbeat arrives in about 25 seconds, the screen tells you and you can try again. The iPhone shows the history stored in the Health app: time in range, the run score and, when available, the map and what the coach said. The starting range can be estimated from your age and resting heart rate. You can use zone 1, zone 2, zone 3 or a range of your own. Scatto is not a medical device and does not replace medical advice. No account, no login and no server. Your run stays on your device and in Health. Scatto does not send your history to iCloud. It is free, with no in-app purchases. To hear the coach on iPhone, use earphones or the speaker. Without them the coach still runs, but you will not hear it.