When the app opens, you will be on the main screen. You will see your Name, GHIN number and current handicap index at the top. (If for some reason it opens on another screen, you can get back there by clicking on the Golf flag icon in the lower left of the bottom navigation bar.) You will see 4 buttons, click on the top right one – HCP Calculator. You must first select the course and set of tees. The number on the left in orange, labelled C.H. is your calculated course handicap for that round.
(For more information on what a course handicap is, go to Handicap 101.)