How to switch between Camera and NFC scanning?

Step 1: 

To access the menu, tap on the 3 line menu icon located at the top left and the menu will show. 

Tap on Settings menu item.

 Step 2:

To select camera, slide the button to the left as shown below.

 Step 3:

To select NFC, slide the button to the right as shown below.

 If NFC is not available on the device, the below message will show.

If NFC was is not enabled in the settings of the app, it can be enabled as well on the screen.

Press and hold the camera Icon for a few seconds, the icon will change to NFC icon, as shown below.