+    public static final long getUsableSpace(String accountName) {
+        File savePath = Environment.getExternalStorageDirectory();
+        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.GINGERBREAD) {
+            return savePath.getUsableSpace();
+            
+        } else {
+            StatFs stats = new StatFs(savePath.getAbsolutePath());
+            return stats.getAvailableBlocks() * stats.getBlockSize();
+        }
+        
+    }