Apparently it has been discovered that guidelines in Android 4.4 for micro SD card They have been updated and basically limit applications to partially write to external storage.
For many, there is the possibility of power access files and folders external memory from a desktop computer takes to errors and problems may occur on the device.
As far as Android is concerned, distinguishing itself from iOS, is that supports external storage as we can see in dozens of devices that are appearing today. And from what can be seen in the new guidelines, Google's goal is to go directly to an internal storage from which you have everything you need for the device, as happens in Nexus devices.
Taking a little bit back in time, when Google opened the doors to external storage from Android 1.1, in Android 4.1 it was limited with a READ_EXTERNAL_STORAGE permission. And with Android 4.4, with the modification of WRITE_EXTERNAL_STORAGE with important limitations in that it can be done in the external storage of the terminal, it seems that it is closing the writing possibilities in the micro SD.
Now the permission will allow selected apps write to SD when they have their own directory. What Google wants is to call the SD card a secondary external storage, and internal storage the primary external storage. So the applications will only be able to read and write in their own directory on the SD, canceling the possibility of reading / writing in other files and folders owned by another application. This measure is for security and what it will mean is that certain file browsers will not be able to create, delete or rename files in SD locations.
A change that is not being very well received by the Android community by taking more control if possible by the Google operating system and that goes against one of his maxims to give more freedom to the user as other OS do not do like iOS.
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