List all fonts available on iOS device in console

ListFonts.m

// List all fonts on iPhone
NSArray *familyNames = [[NSArray alloc] initWithArray:[UIFont familyNames]];

for (NSString *family in familyNames) {
    NSLog(@"Family name: %@", family);
    
    fontNames = [UIFont fontNamesForFamilyName: family];
    for (NSString *font in fontNames) {
        NSLog(@"    Font name: %@", font);
    }
}

ListFonts.swift

let familyNames = UIFont.familyNames

for family in familyNames {
    print("Family name " + family)
    let fontNames = UIFont.fontNames(forFamilyName: family)
    
    for font in fontNames {
        print("    Font name: " + font)
    }
}

You are missing a type declaration for fontNames in ListFonts.m

NSArray *familyNames = [[NSArray alloc] initWithArray:[UIFont familyNames]];
  
for (NSString *family in familyNames) {
  NSLog(@"Family name: %@", family);

  NSArray *fontNames = [UIFont fontNamesForFamilyName: family];
  for (NSString *font in fontNames) {
    NSLog(@"    Font name: %@", font);
  }
}