5 Android KitKat features exclusive to the Nexus 5
1. Low-power audio and sensor batching
Unfortunately, "audio tunneling requires support in the device hardware. Currently audio tunneling is available on Nexus 5 and we're working with our chipset partners to make it available on more devices as soon as possible."
Another exclusive hardware feature of the Nexus 5 are the new step detector and counter sensors. Coupled with the new sensor batching technology on the phone, you have an always-on step counter that can be used in health & fitness apps without draining the battery:
"With sensor batching, Android works with the device hardware to collect and deliver sensor events efficiently in batches, rather than individually as they are detected. This lets the device's application processor remain in a low-power idle state until batches are delivered. You can request batched events from any sensor using a standard event listener, and you can control the interval at which you receive batches. You can also request immediate delivery of events between batch cycles.
Sensor batching is ideal for low-power, long-running use-cases such as fitness, location tracking, monitoring, and more. It can makes your app more efficient and it lets you track sensor events continuously — even while the screen is off and the system is asleep."
2. HDR+ photography
Edges seem so clear-cut compared to the non-HDR+ frames taken with the Nexus 5, that it looks almost unnatural, though the dreaded digital noise that appears with software sharpening seems to be kept largely in check, too. White balance gets off-kilter when using it in low-light scenarios, though, as you can see in our night sample.
3. Full-screen wallpapers with preview
4. Always-on voice-controlled assistance from the home screen
If you have a Nexus 5, however, you can say "OK, Google" right on the home screen, and the voice search function will be launched without you having to even touch the display. It's not the always-on ability we have on phones like the Moto X, which listens to you even in locked state, but it's still bragging rights.
Funny enough, when we forced the Nexus 5 launcher and the new Google Now on something like the Nexus 4, Google's last year pride obtained the same ability to launch voice searches from the homescreen with the "OK, Google" catchphrase.
5. Touchscreen improvements
We'll keep badgering the Mountain View crowd to explain themselves with these unique touchscreen response improvements for the Nexus 5. In the meantime - this is feature number 5 in our list of exclusives that KitKat brings only to Google's finest for the year, so you can sleep tight knowing how unique you will be for getting a Nexus 5.