The Ice Cream Sandwich (4.0) and Jelly Bean (4.1) updates came within very short time difference and there wasn’t much difference feature wise in the two updates. All the features were presented in 4.0 itself but what was new in 4.1 was the level of maturity that the features presented in Jelly Bean were much more matured than in ICS.

1. Android 4.2: New ‘Jelly Beans’ tastes sweeter
The Ice Cream Sandwich (4.0) and Jelly Bean (4.1) updates came within very short
time difference and there wasn’t much difference feature wise in the two updates.
All the features were presented in 4.0 itself but what was new in 4.1 was the level of
maturity that the features presented in Jelly Bean were much more matured than in
ICS.
The biggest improvement one saw in the 4.1 update was Project Butter, which was
the name given to the list of adjustments which enhanced the responsiveness to
touch input by the users. Under these adjustments there was inclusion of triple
buffered graphics which maximizes and renders the clock speed of the CPU in the
device whenever the screen is touched. All the tweaks made the 4.1 update much
more consistent.
It has been 4 months since this update came out and another incremental bump is
out by Android. Android 4.2 is still Jelly Beans. No drastic changes from its
predecessor. However there are enough new features introduced which would keep
android application developer keep hunting for new ideas to take maximum
advantage of the new features.
Single device, multiple users
Multiuser support is the biggest innovation till
date by Android for tablets. Usually tablets are
the devices used my more than one person that
can be anywhere in family, office or someplace
else. Thus it is difficult to keep the data of every
user safe from others. Android realized this issue
and came up with multiuser feature where
different users can configure every detail of the
device starting from home screens to application
settings. For now the feature would be available
only in tablets and not the mobile phones
updating their Android to 4.2.
Enhanced Notification panel
Pull-down notification panel has been a part of the android since its inception. It is
so useful and such a noteworthy feature that iOS 5 update too introduced such panel
for the users. It is a way for the user to keep a tab on what the device is doing.

2. In Android 4.1, the notifications panels were enhanced in such a way that the panels
were expendable and users were able to work within the panels without clicking too
many times. The notifications are no longer deleted unless swiped away or some
action is taken through it.
In Android 4.2, quick settings which are part of other operating systems is used to
change frequently changed settings like brightness, Wi-Fi connectivity, checking
data usage, battery life, Bluetooth toggling, are added in notifications. All these
settings are now available with a single touch which was previously hidden behind
another screen. These notifications and quick settings are also accessible from the
lock screen.
Share on big display
Wireless display is a feature available in
devices using Android 4.2. Share movies,
videos, photos or anything else on a
bigger screen like an HDTV. A wireless
display adapter is to be connected with
HDMI-enabled TV so that whatever your
Android device is displaying is mirrored
on the bigger screen.
Fast, Fluid and smooth
It is the new Jelly Beans but it has buttery
graphics and silky transitions. Don’t get
too excited, it is not some tasty cuisine it
is what the Android 4.2 has in store for the users. As the project butter was already
introduced in 4.1, Android 4.2 takes the legacy further and the switching between
home screens is effortless just like in apps.
The touch responses are more reactive and uniform. Jelly Bean is smart enough to
boost the CPU of the device when the screen is touched and used, reducing it
instantly as soon as the work is done so as to improve the battery life.
Android application developers in India are already claiming this update as the iOS
6 killer with enhancements making all the iPhone features look small.

3. Conclusion:
Though there has been only 4 month gap between the 2 Jelly Bean updates still
Android 4.2 has many good features introduced which are improving usability of the
android devices and continuing its growth as a biggest contender in the smartphone
world.
Meta: Android 4.2 is the new Jelly Bean update by Google. This update has tweaks
changing many things from the last update. It has many good features for Android
powered devices especially for the tablets which got a new feature of multi user.