diff --git a/app/src/main/java/asgardius/page/s3manager/BucketSelect.java b/app/src/main/java/asgardius/page/s3manager/BucketSelect.java
index b60167c..530e61f 100644
--- a/app/src/main/java/asgardius/page/s3manager/BucketSelect.java
+++ b/app/src/main/java/asgardius/page/s3manager/BucketSelect.java
@@ -28,7 +28,8 @@ public class BucketSelect extends AppCompatActivity {
     ArrayList Name;
     ArrayList Img;
     RecyclerView recyclerView;
-    String username, password, endpoint;
+    String username, password, endpoint, prefix;
+    int treelevel;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -36,6 +37,7 @@ public class BucketSelect extends AppCompatActivity {
         endpoint = getIntent().getStringExtra("endpoint");
         username = getIntent().getStringExtra("username");
         password = getIntent().getStringExtra("password");
+        prefix = "";
         setContentView(R.layout.activity_bucket_select);
         Region region = Region.getRegion(US_EAST_1);
         S3ClientOptions s3ClientOptions = S3ClientOptions.builder().build();
@@ -118,10 +120,13 @@ public class BucketSelect extends AppCompatActivity {
     private void explorer(String bucket) {
 
         Intent intent = new Intent(this, ObjectSelect.class);
+        treelevel = 0;
         intent.putExtra("endpoint", endpoint);
         intent.putExtra("username", username);
         intent.putExtra("password", password);
         intent.putExtra("bucket", bucket);
+        intent.putExtra("prefix", prefix);
+        intent.putExtra("treelevel", treelevel);
         startActivity(intent);
 
     }
diff --git a/app/src/main/java/asgardius/page/s3manager/ObjectSelect.java b/app/src/main/java/asgardius/page/s3manager/ObjectSelect.java
index 3617025..7c97441 100644
--- a/app/src/main/java/asgardius/page/s3manager/ObjectSelect.java
+++ b/app/src/main/java/asgardius/page/s3manager/ObjectSelect.java
@@ -19,6 +19,8 @@ import com.amazonaws.services.s3.AmazonS3Client;
 import com.amazonaws.services.s3.S3ClientOptions;
 import com.amazonaws.services.s3.model.Bucket;
 import com.amazonaws.services.s3.model.GeneratePresignedUrlRequest;
+import com.amazonaws.services.s3.model.ListObjectsRequest;
+import com.amazonaws.services.s3.model.ListObjectsV2Request;
 import com.amazonaws.services.s3.model.ListObjectsV2Result;
 import com.amazonaws.services.s3.model.ObjectListing;
 import com.amazonaws.services.s3.model.S3Object;
@@ -26,14 +28,18 @@ import com.amazonaws.services.s3.model.S3ObjectSummary;
 
 import java.net.URL;
 import java.util.ArrayList;
+import java.util.LinkedHashSet;
 import java.util.List;
 
 public class ObjectSelect extends AppCompatActivity {
 
     ArrayList Name;
     ArrayList Img;
+    //ArrayList object;
     RecyclerView recyclerView;
-    String username, password, endpoint, bucket;
+    String username, password, endpoint, bucket, prefix;
+    int treelevel;
+    String[] filename, path;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -42,6 +48,8 @@ public class ObjectSelect extends AppCompatActivity {
         username = getIntent().getStringExtra("username");
         password = getIntent().getStringExtra("password");
         bucket = getIntent().getStringExtra("bucket");
+        prefix = getIntent().getStringExtra("prefix");
+        treelevel = getIntent().getIntExtra("treelevel", 0);
         setContentView(R.layout.activity_object_select);
         Region region = Region.getRegion(US_EAST_1);
         S3ClientOptions s3ClientOptions = S3ClientOptions.builder().build();
@@ -62,29 +70,67 @@ public class ObjectSelect extends AppCompatActivity {
             public void run() {
                 try  {
                     //Your code goes here
-                    List<Bucket> buckets = s3client.listBuckets();
+                    //List<Bucket> buckets = s3client.listBuckets();
+                    ListObjectsRequest orequest = new ListObjectsRequest().withBucketName(bucket).withPrefix(prefix).withMaxKeys(2000);
                     //List<S3Object> objects = (List<S3Object>) s3client.listObjects(bucket, "/");
-                    ListObjectsV2Result result = s3client.listObjectsV2(bucket, "/");
+                    ObjectListing result = s3client.listObjects(orequest);
                     //System.out.println(objects);
                     //This convert bucket list to an array list
-                    Name = new ArrayList<String>();
                     Img = new ArrayList<String>();
+                    LinkedHashSet<String> object = new LinkedHashSet<String>();
                     // Print bucket names
                     //System.out.println("Buckets:");
-                    int i=0;
+                    //int i=0;
                     List<S3ObjectSummary> objects = result.getObjectSummaries();
-                    for (S3ObjectSummary os : objects) {
-                        Name.add(os.getKey());
-                        if (os.getKey().endsWith(".opus") || os.getKey().endsWith(".ogg")
-                                || os.getKey().endsWith(".oga") || os.getKey().endsWith(".mp3")
-                                || os.getKey().endsWith(".m4a")) {
+                    boolean nextbatch = false;
+                    while (result.isTruncated() || !nextbatch) {
+                        if (nextbatch) {
+                            result = s3client.listNextBatchOfObjects (result);
+                            objects = result.getObjectSummaries();
+                        } else {
+                            nextbatch = true;
+                        }
+                        for (S3ObjectSummary os : objects) {
+                            filename = os.getKey().split("/");
+                            if (filename.length == treelevel+1) {
+                                object.add(filename[treelevel]);
+                            }
+                            else {
+                                object.add(filename[treelevel]+"/");
+                            }
+
+                            //i++;
+                        }
+
+                    }
+
+                    Name = new ArrayList<String>(object);
+                    object.clear();
+                    //Img.add(R.drawable.unknownfile);
+                    int i = 0;
+                    while(i<Name.size()) {
+                        //Img.add(R.drawable.unknownfile);
+                        if (Name.get(i).toString().endsWith("/")) {
+                            Img.add(R.drawable.folder);
+                        }
+                        else if (Name.get(i).toString().endsWith(".opus") || Name.get(i).toString().endsWith(".ogg")
+                                || Name.get(i).toString().endsWith(".oga") || Name.get(i).toString().endsWith(".mp3")
+                                || Name.get(i).toString().endsWith(".m4a") || Name.get(i).toString().endsWith(".flac")
+                                || Name.get(i).toString().endsWith(".mka")) {
                             Img.add(R.drawable.audiofile);
                         }
-                        else {
+                        else if(Name.get(i).toString().endsWith(".mp4") || Name.get(i).toString().endsWith(".mkv")
+                                || Name.get(i).toString().endsWith(".webm") || Name.get(i).toString().endsWith(".m4v")) {
                             Img.add(R.drawable.videofile);
                         }
+                        else {
+                            Img.add(R.drawable.unknownfile);
+                        }
+                        i++;
                     }
 
+
+
                     /*for (Bucket bucket : buckets) {
                         //i++;
                         //System.out.println(bucket.getName());
@@ -105,6 +151,8 @@ public class ObjectSelect extends AppCompatActivity {
                             recyclerView.setAdapter(adapter);
                         }
                     });
+                    //System.out.println("tree "+treelevel);
+                    //System.out.println("prefix "+prefix);
 
                 } catch (Exception e) {
                     e.printStackTrace();
@@ -124,11 +172,18 @@ public class ObjectSelect extends AppCompatActivity {
         recyclerView.addOnItemTouchListener(new RecyclerTouchListener(getApplicationContext(), recyclerView, new RecyclerTouchListener.ClickListener() {
             @Override
             public void onClick(View view, int position) {
-                System.out.println("Click on "+Name.get(position).toString());
+                //System.out.println("Click on "+Name.get(position).toString());
                 //explorer(Name.get(position).toString());
-                GeneratePresignedUrlRequest request = new GeneratePresignedUrlRequest(bucket, Name.get(position).toString());
-                URL objectURL = s3client.generatePresignedUrl(request);
-                videoplayer(objectURL.toString());
+                if (Img.get(position).equals(R.drawable.folder)) {
+                    //go to subfolder
+                    explorer(Name.get(position).toString());
+                }
+                else {
+                    //load media file
+                    GeneratePresignedUrlRequest request = new GeneratePresignedUrlRequest(bucket, prefix + Name.get(position).toString());
+                    URL objectURL = s3client.generatePresignedUrl(request);
+                    videoplayer(objectURL.toString());
+                }
             }
 
             @Override
@@ -145,4 +200,40 @@ public class ObjectSelect extends AppCompatActivity {
         startActivity(intent);
 
     }
+
+    private void explorer(String object) {
+
+        Intent intent = new Intent(this, ObjectSelect.class);
+        //treelevel ++;
+        intent.putExtra("endpoint", endpoint);
+        intent.putExtra("username", username);
+        intent.putExtra("password", password);
+        intent.putExtra("bucket", bucket);
+        intent.putExtra("prefix", prefix + object);
+        intent.putExtra("treelevel", treelevel+1);
+        startActivity(intent);
+
+    }
+
+    public void onBackPressed() {
+        if (treelevel >= 2) {
+            path = prefix.split("/");
+            prefix = "";
+            int i = 0;
+            //System.out.println("path "+i);
+            while(i <= path.length-2) {
+                prefix = prefix.concat(path[i]);
+                prefix = prefix.concat("/");
+                //System.out.println("position "+i);
+                i++;
+            }
+        }
+        else if (treelevel == 1) {
+            prefix = "";
+        }
+        treelevel --;
+        //System.out.println("tree "+treelevel);
+        //System.out.println("prefix "+prefix);
+        finish();
+    }
 }
\ No newline at end of file
diff --git a/app/src/main/res/drawable/folder.png b/app/src/main/res/drawable/folder.png
new file mode 100644
index 0000000..b66ede4
Binary files /dev/null and b/app/src/main/res/drawable/folder.png differ
diff --git a/app/src/main/res/drawable/unknownfile.png b/app/src/main/res/drawable/unknownfile.png
new file mode 100644
index 0000000..c507764
Binary files /dev/null and b/app/src/main/res/drawable/unknownfile.png differ