The Sprint HTC One in the U.S is receiving a minor update to the firmware which brings new Sprint ringtones and more importantly, the HD Voice feature. This is a Sprint update, so don’t expect to see a bump in the Android version. Make sure you’re on the lookout for the 1.31.651.2 update over the course of the week. The information was given away by Sprint in a thread on its forum.
Despite receiving this update, the Sprint HTC One continues to be on Android 4.1.2. Some global variants of the HTC One have already received the Android 4.2.2 update while carrier branded versions will certainly be the last to get it.
As far as HD Voice is concerned, it only works with smartphones which already have HD Voice enabled. So the chances are that you might not be able to reap full benefits of this feature, at least for the time being.
Via: Android Police