The app doesn't provide steering guidance directly. (-: There are a few indirect effects of the features that can have a secondary or tertiary effect on steering.
First, the app has an audio option so you don't need to look at the screen. You can specify what is spoken by the app and when. This allows you to use your eyes for steering rather than getting lost in a display. You can chose to view/hear up to 40 metrics at whatever interval of strokes, seconds or meters traveled. You can also have these spoken and/or displayed based on remaining strokes, meters or seconds. The app can determine finish based on the number of strokes, meters or seconds to be rowed or by going to a certain geographic point or a finish line.
If you are rowing to a geographic point or line you can get an idea of course based on the distance traveled versus remaining but that is, obviously, a very crude way to detect gross course errors.
Finally, the app captures your point at each stroke and one of the results display is a map of each piece which can be zoomed in quite tight. You can see minor course changes easily. This displays rating, split, meters traveled and stroke count at whatever interval you desire. You can see examples of this on the screen shots page for the app at or near
http://www.excellentsystems.us/RowExcel/ScreenShots.htm
There are a couple of map displays toward the bottom of that page.
The audio option is probably the most popular option as it frees you from having to look at the screen and allows for better rowing posture. A few folks rowing quads use the Bluetooth speaker so the entire boat can hear the information. One club used the training segment option to run their race plan in a quad. The app allows you to have information spoken based on distances, times or other information.
For what it's worth,
Don Vickers