Like many things in life, it is easy when you know how.

Assuming you have a .otf or .ttf file of your font and you have a license to use it:

  1. Open Finder, locate your font file and drag into Xcode. The Supporting Files folder is a decent place to put them. Make sure the ‘Copy Files if necessary’ is checked.

  2. In the Supporting Files folder there is an Info.plist file. Add a row to the Information Property List dictionary by right clicking and selecting Add Row. The key for the row will be Fonts provided by application which should default to the Array type. To that array add the name of your font file.

Support Files Info.plist screenshot

You should then be able to use your new font style

[UIFontDescriptor fontDescriptorWithFontAttributes: @{
    UIFontDescriptorFamilyAttribute: @"Chivo",
    UIFontDescriptorFaceAttribute: @"Regular"
}];