Sometimes you need to sign or fill out PDF forms while you're away from your Mac. Here's how to get that paperwork done on your iPhone or iPad.

Who Needs to Fill Form W-9? The most common reason for filling out Form W-9 is having income paid to you that you didn’t receive as an employee.

Learn how to fill out a W-4 form accurately to ensure you're withholding the correct amount of income for your taxes.