There are three convienient ways to record a training:
Record workout on Apple Watch
Recording a training on the Apple Watch has the advantage that the heart rate and calories burned are recorded. This is the easiest and recommended way. No more things to consider, just press Start on your wrist and you are good to go. You can leave your iPhone ashore, no waterproof iPhone/case or mounting needed!
Record workout on iPhone (outdoor)
Recording a session on the iPhone works best outdoors. Ensure that either your iPhone is waterproof (iPhone 7 or newer) or that you have a waterproof case for it. Place it somewhere you can reach and see it, but not horizontal and ideally facing in rowing direction as not to confuse the stroke detection algorithm. It is recommended to fasten the iPhone in some way to avoid going overboard.
Mirror mode of Apple Watch on iPhone
When training with the Apple Watch indoor, you can use your iPhone as a screen mirroring the display of your Apple Watch. That way you can follow the workout comfortably without the need to try and sneak peek on your watch. Now any rowing machine comes with your personalized rowing computer!
Starting the mirror mode is very simple, ensure neither Apple Watch nor iPhone are in Flight mode, open RowingCoach on your iPhone and then start your workout on the Apple Watch. The display with your stroke rate and pulse will appear automatically on your iPhone!