How to Sync Lightning Tasks With an iPhone

Download the Provider plugin for Mozilla Thunderbird (see Resources).
Launch Mozilla Thunderbird. Click on 'Tools' and select 'Addons.' Navigate to the location where you saved the Provider plugin, select the file and click 'OK.'
Restart Mozilla Thunderbird.
Launch your browser and navigate to the Google Calendar website (see Resources). Create a Google account if you do not already have one.
Login to Google Calendar. Click on 'Settings,' select the 'Calendars' tab. Click on the calendar you would like to use to sync; if you have no calendars, create one using the appropriate button.
Scroll down the page until you see a line with the header 'Private Address.' Right click on the orange 'XML' button found in that line and select 'Copy Link Address' (or similar, depending on the browser you are using).
Switch back to Mozilla Thunderbird. Click on 'File,' 'New,' and select 'Calendar.'
Select 'On the Network.' Click 'Next.'
Select the 'Google Calendar' radio button. Place your cursor inside the text box labeled 'Location' and press 'CTRL' and 'V' to paste the address you copied from the Google Calendar settings. Click 'Next.' Choose a name and color for the calendar and click 'Next.'
Enter your full Google account name and password. The account name should already be filled in; double-check that it is in the correct format (your_account_name@gmail.com). Click 'OK.'
Switch on your iPhone. Tap 'Settings' and open 'Mail, Contacts, Calendars.'
Tap 'Add Account...' and select 'Microsoft Exchange.'
Enter your full Google account name (your_account_name@gmail.com) in the 'Email' field. Leave the 'Domain' field blank.
Enter your full Google account name (your_account_name@gmail.com) in the 'Username' field. Enter your Google account password in the 'Password' field. Tap 'Next.' Tap 'Cancel' if an 'Unable to Verify Certificate' dialog appears.
Enter 'm.google.com' in the 'Server' field. Tap 'Next.'
Set the 'Calendars' setting to 'On.' Tap 'Done.'
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