Sony's official app is not yet updated for KitKat, but your equipment still works fine
Folks with a Sony Cyber-shot QX lens camera and a Nexus 5 (or KitKat in an unofficial way on other phones) are finding out the hard way that Sony's PlayMemories Mobile application isn't working. It will connect, but it then immediately crashes — which isn't very helpful when you want to take some pictures with a better camera. Sony suggests that this might be possible right in the app description.
[Recommended operating environment]
OS version: Android 2.3 – 4.3
This application is not guaranteed to work on all Smartphones and Tablets.
The good news is there is an easy and free fix with the Camera 360 application. Not only that, but you'll also have a ton of great features that work right with your QX camera, including some very nicely done live effects. There is a reason Camera 360 has over 320,000 five-star ratings in Google Play. It's also my go-to camera app anytime I'm shooting with the QX-10 I have here.
We imagine that Sony will get things sorted in short order, but in the meantime your gear still will work as well (or better) than it ever did. Grab Camera 360 Ultimate from the Google Play link above.