Apple delivered another powerful quarter, even in the absence of a new iPhone, and answered many of the short term question marks over its mobile performance. But even amid such a tour de force, there were issues that may bear the seeds of rockier times ahead, especially in its ability to defend itself against two of its most powerful antagonists, Google and Samsung. There was the cloud ‘ Apple needs to learn lessons here, acknowledged acting CEO Tim Cook, but was vague about which ones. And there was the shift in mobile device growth towards the midmarket, creating dilemmas about how eagerly to sacrifice average selling prices for new markets ‘ and how effective it would be against the growing…