uses iOSapi.Foundation, Macapi.Helpers;

// 不要备份到 iCloud by Aone
function addSkipBackupAttributeToItemAtPath(const Path1: String): Boolean;
var Dir: NSString;
    Url: NSURL;
    ErrorPtr: Pointer;
begin
     Dir := StrToNSStr(Path1);
     Url := TNSURL.Wrap(TNSURL.OCClass.fileURLWithPath(Dir));
     Result := Url.setResourceva lue(TNSNumber.OCClass.numberWithBool(True), NSURLIsExcludedFromBackupKey, @ErrorPtr);
end;

参考：

http://developer.apple.com/library/ios/#qa/qa1719