Although we normally hold our final opinions on a new accessory for our full reviews, LifeProof's Fre ($80 merits this initial tease: this is the thinnest properly-tailored waterproof case we've ever seen for an iPhone -- so interestingly assembled that we could see people using it as an everyday case without even thinking twice. Made from two interlocking layers, each with different types of opaque and transparent plastic inside, Fre easily comes…