Apple's iPhone features Internet access and email compatibility along with basic telephone functions. The iPhone works with a system of mobile applications, more commonly called "apps," that you can download from Apple's App Store. The iPhone comes with basic apps, including Safari, Maps, Weather, iTunes, iPod and Mail, Apple's email client. Mail is compatible with most email accounts, including web mail. The iPhone synchronizes with your computer through iTunes; if you want transfer an email folder to your iPhone, you will need to use the sync system.
Create the folder you want to appear on your iPhone in your email client on your computer. You must have a desktop email client, such as Apple Mail, Mozilla Thunderbird or Microsoft Outlook, in order to create email folders on the iPhone.
Organize your email inbox by transferring relevant emails to the desired folders. You can synchronize as many folders as you like with your iPhone.
Turn your iPhone on and connect it to your computer using a USB cord. Unlock your iPhone if you use a pass code.
Open iTunes if it does not open automatically. Click the device icon for your iPhone, located in the left menu bar.
Click the "Info" tab, located at the top of the iPhone Summary window. Scroll down to "Sync Mail Account." Check the box and select the account where you have create your folders. Select any other email accounts you want on your iPhone.
Click the "Sync" button. Allow your iPhone to synchronize completely before disconnecting.
Tap the "Mail" icon on your iPhone's home screen. Tap the account to verify your folders are now on your iPhone; they should be listed under your inbox.