Horizontal situation indicator - User Manual (iOS)

The HSI shows the current track offset of the current flight plan leg. The scale is +- 5 NM.

Tap the show/hide HSI button to show or hide it:

To select a different inbound course, turn the HSI using your finger.
To sync the HSI back to the current track, tap the top left hand (magenta) field.
To change the HSI position, tap and hold until it increases in size slightly, then drag it to the new location and release your finger.
To change the size of the HSI, use a pinch/zoom gesture.

7.12. Horizontal situation indicator