Several sites are reporting on efforts by XDA Developers forum member schecter7 to improve heat dissipation and reduce the resultant CPU throttling on the Xperia Z3+ using a tinfoil heat sink. It's a pretty good hack, if the figures are to be believed, but seriously, if your phone needs this treatment then its time to switch to something else.
The Snapdragon 810 CPU is at the heart of the Z3+ and has had some pretty bad press around its thermal performance - notably from Samsung. On the evidence of this hack it seems to have been justified.
However part of me wonders whether the real problem isn't Android and the way that its loading of features and design elements makes greater and greater demands on hardware. We're seeing 4GB of RAM becoming the new benchmark for Android phones, on top of CPUs that would do reasonable duty on a desktop PC. Doesn't stop them stuttering or feeling sluggish in use.
Google needs to address this at source. Slimming Android down and working to boost its efficiency and responsiveness. Both Apple and Microsoft have managed to do this with their mobile platforms, delivering devices that run beautifully on comparatively modest hardware.
As far as Sony is concerned, I'm amazed that this phone made it out of the test lab. Surely some effort was made to measure heat and its impact on performance? Releasing half-baked devices which generate headlines like this aren't going to help it regain its good name.