Lynda.com and iMore both have tutorials and guides available on their websites for users of most versions of the iPhone. While iMore is free, Lynda.com only offers 10 free days of usage as of 2015. Once the 10 days are over, users must subscribe or deactivate their accounts.
Guides on the site cover a wide range of iPhone features such as checking email, using Siri and operating the built-in camera. iMore features in-depth written articles detailing how to use all of these features and more, while Lynda.com provides video tutorials. While both of these websites offer iPhone tutorials, they also cater to users of iPads, Apple watches and Macs as well.