Who runs the phone? Battery!

Removing the battery from the S6 should be a little bit easier than from the Edge. In the Edge, the battery cable was routed under the motherboard before connecting on top, necessitating removing the motherboard to get to the battery.

Looks like with the bit of extra room inside the regular S6, Samsung was able to run the cable on top of the board, to save a step for battery removal.

Also, thanks to the flat-screen design of the S6, it's easier to push an opening pick straight into the gap between the battery and display assembly, making it easier to cut the (just-as-strong) adhesive holding the battery.

This hardly qualifies as a user-replaceable battery, but it is a bit easier than in the S6 Edge. Still, it's a flying leap backwards from previous Galaxies like the S5, where you could replace the battery using nothing but your wits, and you didn't even really need those.