How to Create a Label in Android Email
Any cellphone that runs on the Android mobile operating system requires the user to sign in with a Google Account and uses Gmail as the default email service. In lieu of folders, Gmail lets users categorize their email with labels. Since your Gmail account syncs with your Android device, any labels you create through Gmail will be added to the Email app on your Android device. This means you can create labels for Android Email from your Web browser.
Open your browser and navigate to Gmail.com. Type your Google Account login credentials in the applicable fields and click the "Sign In" button to log in your account.
Click the "gear" icon in the upper-right corner of your Gmail home page and select the "Mail Settings" option from the drop-down menu.
Click the "Labels" tab and then click the "Create new label" button.
Type a name for the new label in the space provided. If you want to make the label a sub-label, click the arrow beneath the "Nest label under:" heading and select the container label from the drop-down menu.
Click the "Create" button to create the label. The label will be added to the Email application on your Android device.