Apple's iPhone 5 is rapidly approaching its first birthday, so speculation about Apple's next-generation iPhone, dubbed iPhone 5S or iPhone 6, is hot topic right now. Here, we ask whether or not it is worth buying an iPhone 5 now or waiting until Apple launches a new iPhone (or two) later this year.Related StoriesLeaked parts round-up: iPad 5 display, iPhone 5S camera, iPhone 5C shell, iPhone 5G?Should I buy an iPad mini or an iPad 4?