OnePlus has launched the "Sandstone" case for Apple's iPhone 6 and 6s, and guess what's inside? An invitation to purchase the OnePlus X. You have to admire the sheer chutzpah of that, though it's hard to imagine many folks turfing their $649-plus iPhone 6s for a $249 OnePlus X. Random buyers of the case will get an invite for the rare ceramic version of the OnePlus X, while a select few will actually get the new model for free. The One X has often been compared to older iPhones, so the case does make a strange kind of sense -- and it also makes the iPhone much less slippery. Making Apple owners aware of the product might pose more of a challenge, but the company is nothing if not savvy at marketing.