"It used to be possible for Android apps to access any kind of storage on an android device through the WRITE_EXTERNAL_STORAGE permission. Writing to the SD card is useful for many different kinds of apps, e.g. file managers or cloud storage synchronization. However, the latest version of Android will no longer allow apps to write anywhere on external storage media, instead apps will only be allowed to access app-specific folders on SD cards. Android Police has an excellent writeup of the changes and the implications for users."
[ED Note: This is bound to irritate power users that rely on their SD cards for additional device storage.]
(Score: 3, Informative) by Namarrgon on Thursday February 20 2014, @02:01AM
First, as some have said, apps with the appropriate permission can still read from SD cards. So your common books, photos, downloads folders etc are still accessible.
Second, as the article mentions, Kitkat also introduces the Storage Access Framework [android.com]. With this API, a DocumentProvider [android.com] can manage files and make them available for read and write access by client apps, whether located on a local SD card, LAN, cloud server, or elsewhere.
Why would anyone engrave Elbereth?