One of the biggest new features of iOS 7 from a user experience standpoint is the ability to adjust OS-wide text formatting. This includes increasing the font weight (bold) and text size. These settings can be set in the device's settings application. Although it is not a requirement to support dynamic type, it is recommended to do so! Here is an example of these settings:

When typically dealing with fonts, we specify the font family name and the size we want to set, as follows:

[UIFont fontWithName:@"HelveticaNeue" size:19.0f]

When working with dynamic type, we will use fonts with styles instead of using the literal name of any font unlike the preceding code. UIFont has been equipped with a new method called preferredFontForTextStyle. This loads the selected font preferences from the user's device and sets the text to the given style. Here is an example of the multiple font styles:

The text on the left-hand side is the smallest size able to be rendered, the middle text is the largest...