How to get to toolbar action buttons settings: Open Left Main Menu → Settings → User Interface → Toolbar Action Buttons. Or you can customize Toolbar Action Buttons by tapping on … toolbar action button in top toolbar of map screen, then scrolling down in menu and tapping on Customize menu item. Toolbar Action Buttons are simply customizable shortcuts to various functions of GPX Viewer. You can choose various functions which will be available on top toolbar of map screen of GPX Viewer. Image below is highlighting Toolbar Action Buttons in GPX Viewer screen.