The settings panel can be activated by pressing the button at the top-left of the main interface. The following image annotates the settings button.

The image below shows the settings panel.

As can be seen above, it has three sections:

• Phone:  Allows you to rectify phone number.
• Map: Allows you to finely control various mapping options. More about this here.
• About: Gives you read-only general information.

The following video demonstrates activating the settings panel and rectifying phone number.