I think it actually goes to the Pre, then Nexus S, and finally the Moto X. The Pre had it’s problems, largely the longevity of the slider mechanism and the side buttons (ignoring Sprint exclusivity and Palm dying). Mine died with the volume up button getting stuck on, constantly notifying me that the volume was at max. But it was essentially a fidget toy, I couldn’t stop spinning and flipping that thing. I think a big part of it was the thickness, around 16mm thick while the Nexus S and Moto X were around 10mm thick. Combined with the smaller size, it really was shaped like a river stone, while the other two just borrowed the sculpting to force into a different form factor.

So, we ended up with the Nexus S being a little bigger, and a little less sculpted. And then the Moto X was much more in the direction of modern phones, with just enough sculpting to make it nice to hold. Still tiny by today’s standards, and honestly, my ideal is probably somewhere between the Moto X and Nexus 5, with modern screen coverage ratios.