When Google's Android chief Sundar Pichai announced the upcoming release of Android 4.4 with an image of a giant KitKat-themed Android, it seemed that Nestle's chocolate snack would provide the next Android OS name, and replace the previous 4.4 codename Key Lime Pie.

A recent leak of one early version of Android 4.4, believed to predate Pichai's 3 September announcement, showed a slice of lime and no hint of KitKat. 

So far, the drip feed of information on the yet-to-launch-OS suggests new features including better support for wireless printing from Android devices and possibly native NFC payment options, rather than only third-party enabled capabilities.

This latest set of leaked images from another release of KeyLimePie/KitKat suggest these features and more are likely to arrive in Android 4.4.

The image above is of the Android build running on the Nexus 7 2013 model .

The overall assessment is that 4.4 seems to be a more polished version of the Android platform than has been seen in the past, with a feature set that more closely resembles iOS devices out of the box. As Google has said previously, with KitKat it's aiming for the mainstream and this may be its best shot yet shot at tempting loyal iOS users to give it a go.

It looks like Google is introducing a moving mosaic of its Android heritage, showcasing its sugar-coated and alphabetically ordered OS timeline: Cup Cake (1.5), Donut (1.6), Eclair (2.0), Froyo (2.2), Gingerbread (2.3), Honeycomb (3.0), Ice Cream Sandwich (4.0), Jelly Bean (4.1) and KitKat/Key Lime Pie (4.4).

It's accessed by pressing and holding on the red KitKat logo.

Lollipop anyone?

At first glance 4.3.1 (left) and 4.4 (right) look the same, but icons for YouTube, Settings, Google Settings, Google and Voice search change. Google+ Photos also pops up in 4.4 while Messenger disappears. And there's the addition of QuickOffice of course.

Consistent with the previous leaks, it looks like Google's Android team has put some effort into easier printing from Android devices beginning with KitKat.

Shown above is an option to turn on Cloud Print, presumably the Google service launched earlier this year, which enables print jobs to be sent from tablets, phones and notebooks over the web.  

The settings icon has changed from 4.3, and in this version Google looks to have implemented a Tap and Pay feature. Exactly what Google has here isn't known yet, but it would appear to suggest better support for NFC-based payments. Interestingly, Google recently opened up Google Wallet to all Android devices running 2.3 or higher, even on hardware without NFC support. 

Google's Tap and Pay isn't enabled here so it's hard to say if it's working or not.

This one is odd. The Android version screen looks nothing like the recent Key Lime Pie leak from Gadget Helpline, while the background is the same as Jelly Bean 4.3, but obviously there's a big K there. 

On the left is the clock in Android Jelly Bean 4.3.1. On the right is KitKat's clock, which is more balanced than Jelly Bean. Besides toning down the hour font, the alarm clock migrates from the bottom in of the screen to the top left in KitKat. 

Here's QuickOffice implemented in KitKat. It makes sense to ship the app with Android, given that Google made it free last month  and with Android can ramp up its user numbers and keep Microsoft Office on the outer. 

On the left is 4.3.1 and on the right is 4.4. Again, KitKat loses screaming first digit and is more centred. KitKat's stopwatch is visually less cluttered, doing away with the minute and second markers.  

Google has made similar design changes in the timer app. In the left is the Jelly Bean's timer, on the right is KitKat's. 

Jelly Bean Downloads (left) versus KitKat Downloads.