Sony Xperia (compact): does pressing camera button only work within camera app?

[omega3]

I'm considering buying the Xperia XZ1 Compact and was wondering if you hold the phone and accidentally press the dedicated camera button, will this take a picture even when you're not in the camera app or how does that work?

Second, how good is the XZ1 camera in low light situations? Is it as good as the Galaxy S7? Any tips for taking good low light pics with the Xperia?

Thanks in advance for all good feedback!

 

[wilds]

Yes, I believe the camera app has the option to disable quick launch.

Even if it didn't, an unrooted device has the ability to remap keys.