The internals of phones are almost completely battery now, which is what makes the weight. The stainless on the X does make some difference, but the trend is to make smaller electronics with more battery. Battery density is directly correlated with the amount of power they can hold, so if anything weight will go up, not down.My personal beef with modern iPhones is less about their size and more about their weight. When are they going to make iPhones with lighter materials?