This isn't always the case in the Android world, where device manufacturers' partnerships with carriers mean that phones tend to be packed full of "bloatware" that needs to be updated along with the Android OS. Doing so is not usually a priority for the carriers, who would rather that you just buy a new phone every couple of years (preferably more often). Google's Nexus devices, especially the ones you buy off-contract, are updated more often, but they also aren't heavily promoted by the carriers; partly because of this,of the world's Android devices are running the latest "Jelly Bean" version.
Three smartphones on three separate carriers, however, are about to join that 15 percent: Sprint'sVerizon'sand
What new features will the update add?
Each phone's update page lists some of the improvements in Android 4.1 Jelly Bean. More are listed onfor this Android version. The biggest improvement isn't a feature so much as a performance upgrade; called Google's "Project Butter," it vastly improves the speed at which your phone responds to your touch, which means less lag and smoother animations.
Butter-flavored jelly beans are not included with the software update.
Does the update add any new apps?
The new Google Now app works a lot like the iPhone's Siri, and also features "cards" which show you what's going on around you (like travel time to your home or work). Also, the camera app has been "completely redesigned" for Jelly Bean, and now features the Photo Sphere panoramic option.
Are there any updates which are unique to each phone?
On Sprint's LG Optimus S, the Browser app is being replaced by Google's Chrome browser, if you aren't using it already. It has features including a bookmark sync with the desktop version of Chrome.
On Verizon's Motorola Droid RAZR, a lot of Motorola's "bloatware" apps are being removed, like MOTOACTV and Verizon Video on Demand. The Motorola Gallery and Music apps are being replaced by the Google versions used on most Android devices.
On AT&T's HTC One X, a number of AT&T-branded apps are being added, including the Dropbox clone AT&T Locker.
Jared Spurbeck is an open-source software enthusiast, who uses an Android phone and an Ubuntu laptop PC. He has been writing about technology and electronics since 2008.