Good morning. This is my last morning writing to you for a while, as Dan DeFrancesco returns from leave on Monday! But I'll still be around: After a brief staycation (the lawn needs tending to), I'll be back behind the scenes editing each edition from London. In today's big story, we're looking at the key details from Apple's earnings report — and why the company's huge stream of App Store revenue could be at risk.Newsletter alert: BI Tech Memo is a weekly newsletter where Silicon Valley secrets go public. ...