Google has launched its all new Camera app on the Play Store, finally bringing features like Photo Sphere, Panorama, the new Lens Blur, and an updated UI, to non-Nexus devices.

Google Camera features:
• Photo Spheres for immersive 360º views
• Lens Blur mode for SLR-like photos with shallow depth of field
• Panorama mode with high resolution
• 100% viewfinder for getting the maximum resolution from the sensor (no dropped pixels)
• Updated UI that gets out of your way and is centered on an extra large capture button
• Works on phones and tablets running Android 4.4+ KitKat

The Google Camera app is now available on the Play Store (http://goo.gl/llsZjx), and currently works on all phones and tablets running Android 4.4+ KitKat.
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Right now it only works with Nexus devices …..
I agree that making the camera app independent of the OS make it faster to push updates to the app itself.
It is working with KK updated LG G2s.