A better camera, sharper display and faster charging put Samsung’s new flagship phones ahead in the smartphone race. In this unpredictable world, it’s the constants in life that I can count on. The sun rises in the East, Starbucks lattes always taste the same, and Apple’s iPhones are always better than Samsung’s Galaxy phones. Since the dawn of the smartphone wars, there have been basic truths about Samsungs: They’re made of flimsy plastic, their cameras can’t keep up with the iPhone’s, and their modified Android software is ugly and intolerably cluttered. With the Galaxy S6 and S6 Edge, which arrive...