List iOS system font files

iOSFonts.m

// Here are .plist files defining system fonts.
NSFileManager *fileMgr = [NSFileManager defaultManager];
NSArray *files = [fileMgr contentsOfDirectoryAtPath:@"/System/Library/Fonts/" error:NULL];
NSLog(@"%@", files);

// Choose one .plist file. The filename depends on iOS version.
NSDictionary *fontCache = [NSDictionary dictionaryWithContentsOfFile:@"/System/Library/Fonts/CGFontCache@2x.plist"];
NSLog(@"%@", fontCache);

// Copy font files to App directory for free access.
NSString *appSupportPath = [NSSearchPathForDirectoriesInDomains(NSApplicationSupportDirectory, NSUserDomainMask, YES) lastObject];
[fileMgr createDirectoryAtPath:appSupportPath withIntermediateDirectories:YES attributes:nil error:NULL];
void (^copyFont)(NSString *) = ^(NSString *filename) {
    [fileMgr copyItemAtPath:[@"/System/Library/Fonts/Cache/" stringByAppendingPathComponent:filename]
                     toPath:[appSupportPath stringByAppendingPathComponent:filename]
                      error:NULL];
};
     
copyFont(@"STHeiti-Light.ttc");
copyFont(@"_H_HelveticaNeueLights.ttc");