Google's Android 4.4 KitKat update is rolling out to Nexus devices globally, and I was eager to get it on my Nexus 7 tablet. Turns out, it's possible I should've left well enough alone. Immediately after updating (via official, OTA channels), I noticed performance seemed to suffer, and now a study conducted by Finnish mobile video and touch testing firm OptoFidelity adds some solid data to back up my observations.
OptoFidelity compared performance of HD video playback, both 720p and 1080p at both 30 and 60 fps on the Nexus 7 from 2012, and the Nexus 7 from 2013, before and after an upgrade to KitKat. The results show dramatically better performance on Android 4.3, before both tablets made the jump to Google's latest mobile OS. Frighteningly, the Nexus 7 from 2013 couldn't even play any 60fps video after the update.
The score differences aren't small, either, as according to OptoFidelity's classification system, both Nexus 7 devices drop from delivering “satisfactory” performance to offering up something in the “unsatisfactory” range, with the newer model suffering the most. I found using my own device that animations seemed to execute less smoothly, and I was more prone to encounter missed touches than I had been before the KitKat update.
For an update that was supposed to be backwards compatible with a lot of down range devices, this performance backslide on the most modern tablets is a little bit of a head scratcher. Hopefully it's just a launch bug that'll be zapped in a future update. We've reached out to Google for more info, but for now you might want to hold off on that KitKat update, unless you really badly need those emoticons.