4.4.2 SDCard directories - help have Samsung s5, rooted.
I need your help to understand something..
Here is my directories related to storage SDCard

/sdcard -&gt; /storage/emulated/legacy (SymLink)
/mnt/extSdCard -&gt; /storage/extSdCard (Symlink)
/mnt/sdcard -&gt; /storage/emulated/legacy (Symlink)
/storage/sdcard0 -&gt; /storage/emulated/legacy (Symlink)
/storage/extSdCard mounted to the SD-Card
/storage/emulated/legacy mounted to the internal storage
/storage/emulated/0 mounted to the internal storage


So only /storage/extSdCard is the real sdcard.  

It is not seems to be right.. how can Applications know where to write to?
For example, Whatsup cannot find the SD for some reason - I believe it related to this issue..

what do you think of it?
Applications don't have to care where the storage is. They just ask the Android system to give them a "pointer" to it. There are specific API calls for this, like getExternalStorageDirectory(). For details, you might check on our sister site: Get the right external storage from Android devices.