From the iPhone 5 teardown: "The battery comes out with a bit of prying once the front panel is removed." And there are no warnings that you shouldn't remove the battery and that to replace the battery you will need a whole new back assembly.

And I guess that's ignoring the fact that phones are expected to be hard to take apart whereas iFixit complained loudly about the non-repairability of the iMac. http://www.ifixit.com/Teardown/iMac+Intel+21.5-Inch+EMC+2544...