While Android 4.4 “KitKat” will be releasing soon, there is very little information on new features. One major change will be that Android 4.4 will allow only a single app to manage all the text messages (SMS) on your phone. This single app will be the default app chosen only by the user.
Currently, what happens is that more than one app manages SMS messages on Android. In a new blog post for Android developers, Google advises app developers to get their apps to check if it is the default app and if not, then prompt users to select a default one. This means users will basically give access to their SMS messages to a single app.
What is Google planning with this change?
Google might be introducing a new feature with their Hangouts app to handle SMS on the phone. This is a big deal because if Hangouts manage SMS on a phone, it can potentially synchronize those messages on Chrome.
Getting Hangouts to manage all types of messaging, is something Google will definitely introduce. Hangouts will then probably become somewhat similar to what iMessages is on Apple’s various platforms.
Source: Android Developers Blog