diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 76675bfd..e8aff7c2 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -5,6 +5,7 @@
 
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
 
     <application
         android:allowBackup="true"
diff --git a/app/src/main/java/org/mian/gitnex/activities/FileViewActivity.java b/app/src/main/java/org/mian/gitnex/activities/FileViewActivity.java
index 19ed4c6b..557b537c 100644
--- a/app/src/main/java/org/mian/gitnex/activities/FileViewActivity.java
+++ b/app/src/main/java/org/mian/gitnex/activities/FileViewActivity.java
@@ -1,13 +1,21 @@
 package org.mian.gitnex.activities;
 
 import android.content.Context;
+import android.content.pm.PackageManager;
 import android.graphics.BitmapFactory;
+import android.graphics.Typeface;
 import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.Drawable;
+import android.os.Build;
 import android.os.Bundle;
+import android.os.Environment;
 import android.text.method.ScrollingMovementMethod;
 import android.util.Base64;
 import android.util.Log;
+import android.view.Gravity;
+import android.view.Menu;
+import android.view.MenuInflater;
+import android.view.MenuItem;
 import android.view.View;
 import android.widget.ImageView;
 import android.widget.LinearLayout;
@@ -15,6 +23,8 @@ import android.widget.ProgressBar;
 import android.widget.TextView;
 import androidx.annotation.NonNull;
 import androidx.appcompat.widget.Toolbar;
+import androidx.core.app.ActivityCompat;
+import androidx.core.content.ContextCompat;
 import com.github.barteksc.pdfviewer.PDFView;
 import com.github.barteksc.pdfviewer.util.FitPolicy;
 import com.github.chrisbanes.photoview.PhotoView;
@@ -23,13 +33,18 @@ import com.pddstudio.highlightjs.models.Theme;
 import org.apache.commons.io.FilenameUtils;
 import org.mian.gitnex.R;
 import org.mian.gitnex.clients.RetrofitClient;
+import org.mian.gitnex.fragments.BottomSheetFileViewerFragment;
 import org.mian.gitnex.helpers.AlertDialogs;
 import org.mian.gitnex.helpers.Toasty;
 import org.mian.gitnex.models.Files;
 import org.mian.gitnex.util.AppUtil;
 import org.mian.gitnex.util.TinyDB;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
 import java.io.UnsupportedEncodingException;
 import java.net.URLDecoder;
+import java.util.Objects;
 import retrofit2.Call;
 import retrofit2.Callback;
 
@@ -37,7 +52,7 @@ import retrofit2.Callback;
  * Author M M Arif
  */
 
-public class FileViewActivity extends BaseActivity {
+public class FileViewActivity extends BaseActivity implements BottomSheetFileViewerFragment.BottomSheetListener {
 
     private View.OnClickListener onClickListener;
     private TextView singleFileContents;
@@ -51,6 +66,7 @@ public class FileViewActivity extends BaseActivity {
     private LinearLayout pdfViewFrame;
     private byte[] decodedPdf;
     private Boolean pdfNightMode;
+    private static final int PERMISSION_REQUEST_CODE = 1;
 
     @Override
     protected int getLayoutResourceId(){
@@ -90,6 +106,8 @@ public class FileViewActivity extends BaseActivity {
         initCloseListener();
         closeActivity.setOnClickListener(onClickListener);
 
+        tinyDb.putString("downloadFileContents", "");
+
         try {
 
             singleFileName = URLDecoder.decode(singleFileName, "UTF-8");
@@ -134,6 +152,10 @@ public class FileViewActivity extends BaseActivity {
                         String fileExtension = FilenameUtils.getExtension(filename);
                         mProgressBar.setVisibility(View.GONE);
 
+                        // download file meta
+                        tinyDb.putString("downloadFileName", filename);
+                        tinyDb.putString("downloadFileContents", response.body().getContent());
+
                         if(appUtil.imageExtension(fileExtension)) { // file is image
 
                             singleFileContentsFrame.setVisibility(View.GONE);
@@ -186,6 +208,18 @@ public class FileViewActivity extends BaseActivity {
                                     .nightMode(pdfNightMode)
                                     .load();
 
+                        }
+                        else if (appUtil.excludeFilesInFileViewerExtension(fileExtension)) { // files need to be excluded
+
+                            imageView.setVisibility(View.GONE);
+                            singleCodeContents.setVisibility(View.GONE);
+                            pdfViewFrame.setVisibility(View.GONE);
+                            singleFileContentsFrame.setVisibility(View.VISIBLE);
+
+                            singleFileContents.setText(getResources().getString(R.string.excludeFilesInFileviewer));
+                            singleFileContents.setGravity(Gravity.CENTER);
+                            singleFileContents.setTypeface(null, Typeface.BOLD);
+
                         }
                         else { // file type not known - plain text view
 
@@ -239,6 +273,113 @@ public class FileViewActivity extends BaseActivity {
 
     }
 
+    @Override
+    public boolean onCreateOptionsMenu(Menu menu) {
+        MenuInflater inflater = getMenuInflater();
+        inflater.inflate(R.menu.generic_nav_dotted_menu, menu);
+        return true;
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+
+        int id = item.getItemId();
+
+        switch (id) {
+            case android.R.id.home:
+                finish();
+                return true;
+            case R.id.genericMenu:
+                BottomSheetFileViewerFragment bottomSheet = new BottomSheetFileViewerFragment();
+                bottomSheet.show(getSupportFragmentManager(), "fileViewerBottomSheet");
+                return true;
+            default:
+                return super.onOptionsItemSelected(item);
+        }
+
+    }
+
+    @Override
+    public void onButtonClicked(String text) {
+
+        switch (text) {
+            case "downloadFile":
+
+                if (Build.VERSION.SDK_INT >= 23)
+                {
+                    if (checkPermission())
+                    {
+                        requestFileDownload();
+                    }
+                    else {
+                        requestPermission();
+                    }
+                }
+                else
+                {
+                    requestFileDownload();
+                }
+                break;
+
+        }
+
+    }
+
+    private void requestFileDownload() {
+
+        final TinyDB tinyDb = new TinyDB(getApplicationContext());
+
+        if(!tinyDb.getString("downloadFileContents").isEmpty()) {
+
+            File outputFileName = new File(tinyDb.getString("downloadFileName"));
+            final File downloadFilePath = new File(Environment.getExternalStorageDirectory().getPath() + "/Download/" + outputFileName.getName());
+
+            byte[] pdfAsBytes = Base64.decode(tinyDb.getString("downloadFileContents"), 0);
+            FileOutputStream fileOutputStream = null;
+
+            try {
+
+                fileOutputStream = new FileOutputStream(downloadFilePath, false);
+                Objects.requireNonNull(fileOutputStream).write(pdfAsBytes);
+                fileOutputStream.flush();
+                fileOutputStream.close();
+                Toasty.info(getApplicationContext(), getString(R.string.downloadFileSaved));
+
+            }
+            catch (IOException e) {
+                Log.e("errorFileDownloading", Objects.requireNonNull(e.getMessage()));
+            }
+
+        }
+        else {
+            Toasty.error(getApplicationContext(), getString(R.string.waitLoadingDownloadFile));
+        }
+
+    }
+
+    private boolean checkPermission() {
+        int result = ContextCompat.checkSelfPermission(this, android.Manifest.permission.WRITE_EXTERNAL_STORAGE);
+        return result == PackageManager.PERMISSION_GRANTED;
+    }
+
+    private void requestPermission() {
+        ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.WRITE_EXTERNAL_STORAGE}, PERMISSION_REQUEST_CODE);
+    }
+
+    @Override
+    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
+        switch (requestCode) {
+            case PERMISSION_REQUEST_CODE:
+                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
+                    Log.i("PermissionsCheck", "Permission Granted");
+                }
+                else {
+                    Log.e("PermissionsCheck", "Permission Denied");
+                }
+                break;
+        }
+    }
+
     private void initCloseListener() {
         onClickListener = new View.OnClickListener() {
             @Override
@@ -249,4 +390,4 @@ public class FileViewActivity extends BaseActivity {
         };
     }
 
-}
+}
\ No newline at end of file
diff --git a/app/src/main/java/org/mian/gitnex/fragments/BottomSheetFileViewerFragment.java b/app/src/main/java/org/mian/gitnex/fragments/BottomSheetFileViewerFragment.java
new file mode 100644
index 00000000..b8ea4c4b
--- /dev/null
+++ b/app/src/main/java/org/mian/gitnex/fragments/BottomSheetFileViewerFragment.java
@@ -0,0 +1,57 @@
+package org.mian.gitnex.fragments;
+
+import android.content.Context;
+import android.os.Bundle;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.TextView;
+import com.google.android.material.bottomsheet.BottomSheetDialogFragment;
+import org.mian.gitnex.R;
+
+/**
+ * Author M M Arif
+ */
+
+public class BottomSheetFileViewerFragment extends BottomSheetDialogFragment {
+
+    private BottomSheetFileViewerFragment.BottomSheetListener bmListener;
+
+    @Nullable
+    @Override
+    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
+
+        View v = inflater.inflate(R.layout.bottom_sheet_file_viewer, container, false);
+
+        TextView downloadFile = v.findViewById(R.id.downloadFile);
+
+        downloadFile.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                bmListener.onButtonClicked("downloadFile");
+                dismiss();
+            }
+        });
+
+        return v;
+    }
+
+    public interface BottomSheetListener {
+        void onButtonClicked(String text);
+    }
+
+    @Override
+    public void onAttach(@NonNull Context context) {
+        super.onAttach(context);
+
+        try {
+            bmListener = (BottomSheetFileViewerFragment.BottomSheetListener) context;
+        } catch (ClassCastException e) {
+            throw new ClassCastException(context.toString()
+                    + " must implement BottomSheetListener");
+        }
+    }
+
+}
diff --git a/app/src/main/java/org/mian/gitnex/helpers/Toasty.java b/app/src/main/java/org/mian/gitnex/helpers/Toasty.java
index df68e5f1..f8080296 100644
--- a/app/src/main/java/org/mian/gitnex/helpers/Toasty.java
+++ b/app/src/main/java/org/mian/gitnex/helpers/Toasty.java
@@ -28,4 +28,19 @@ public class Toasty {
 
     }
 
+    public static void error(Context context, String message) {
+
+        LayoutInflater inflater = LayoutInflater.from(context);
+        View view = inflater.inflate( context.getResources().getLayout(R.layout.custom_toast_error), null );
+
+        TextView text = view.findViewById(R.id.toastText);
+        text.setText(message);
+
+        Toast toast = new Toast(context);
+        toast.setDuration(Toast.LENGTH_LONG);
+        toast.setView(view);
+        toast.show();
+
+    }
+
 }
diff --git a/app/src/main/java/org/mian/gitnex/util/AppUtil.java b/app/src/main/java/org/mian/gitnex/util/AppUtil.java
index 647e27c5..71451f9f 100644
--- a/app/src/main/java/org/mian/gitnex/util/AppUtil.java
+++ b/app/src/main/java/org/mian/gitnex/util/AppUtil.java
@@ -218,7 +218,8 @@ public class AppUtil {
                 "coffee", "rc", "rs", "rust", "basic", "clj", "css", "dart", "lisp", "erl", "hs", "lsp", "rkt",
                 "ss", "llvm", "ll", "lua", "matlab", "pascal", "r", "scala", "sql", "latex", "tex", "vb", "vbs",
                 "vhd", "tcl", "wiki.meta", "yaml", "yml", "markdown", "xml", "proto", "regex", "py", "pl", "js",
-                "html", "htm", "volt", "ini", "htaccess", "conf", "gitignore", "gradle", "txt", "properties", "bat"};
+                "html", "htm", "volt", "ini", "htaccess", "conf", "gitignore", "gradle", "txt", "properties", "bat",
+                "twig"};
 
         return Arrays.asList(extValues).contains(ext);
 
@@ -240,6 +241,16 @@ public class AppUtil {
 
     }
 
+    public Boolean excludeFilesInFileViewerExtension(String ext) {
+
+        String[] extValues = new String[] {"doc", "docx", "ppt", "pptx", "xls", "xlsx", "xlsm", "odt",
+                "ott", "odf", "ods", "ots", "exe", "jar", "odg", "otg", "odp", "otp", "bin", "dmg", "psd",
+                "xcf"};
+
+        return Arrays.asList(extValues).contains(ext);
+
+    }
+
     public String getLastCharactersOfWord( String str, int count ) {
 
         return str.substring(str.length() - count);
diff --git a/app/src/main/res/drawable/ic_file_download_24dp.xml b/app/src/main/res/drawable/ic_file_download_24dp.xml
new file mode 100644
index 00000000..ffc2a2ff
--- /dev/null
+++ b/app/src/main/res/drawable/ic_file_download_24dp.xml
@@ -0,0 +1,5 @@
+<vector android:autoMirrored="true" android:height="24dp"
+    android:tint="#368F73" android:viewportHeight="24.0"
+    android:viewportWidth="24.0" android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="#FF000000" android:pathData="M19,9h-4V3H9v6H5l7,7 7,-7zM5,18v2h14v-2H5z"/>
+</vector>
diff --git a/app/src/main/res/layout/bottom_sheet_file_viewer.xml b/app/src/main/res/layout/bottom_sheet_file_viewer.xml
new file mode 100644
index 00000000..180ffd3d
--- /dev/null
+++ b/app/src/main/res/layout/bottom_sheet_file_viewer.xml
@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="vertical"
+    android:paddingBottom="8dp"
+    android:background="?attr/primaryBackgroundColor"
+    android:paddingTop="8dp">
+
+    <androidx.core.widget.NestedScrollView
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content">
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:orientation="vertical"
+            android:layout_height="wrap_content">
+
+            <TextView
+                android:id="@+id/downloadFile"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_gravity="center_vertical"
+                android:text="@string/downloadFile"
+                android:drawableStart="@drawable/ic_file_download_24dp"
+                android:drawablePadding="24dp"
+                android:textColor="?attr/primaryTextColor"
+                android:textSize="16sp"
+                android:padding="16dp" />
+
+        </LinearLayout>
+
+    </androidx.core.widget.NestedScrollView>
+
+</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/custom_toast_error.xml b/app/src/main/res/layout/custom_toast_error.xml
new file mode 100644
index 00000000..7bd724f3
--- /dev/null
+++ b/app/src/main/res/layout/custom_toast_error.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/custom_toast_container"
+    android:orientation="horizontal"
+    android:layout_width="fill_parent"
+    android:layout_height="fill_parent"
+    android:padding="15dp"
+    android:background="@drawable/round_corners"
+    android:backgroundTint="@color/toastBackground">
+
+    <TextView android:id="@+id/toastText"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:textColor="@color/darkRed"
+        android:layout_gravity="center"
+        android:gravity="center" />
+
+</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 1af444d0..1660770a 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -551,4 +551,8 @@
     <string name="mergePRSuccessMsg">Pull Request was merged successfully</string>
     <string name="mergePR404ErrorMsg">Pull Request is not available for merge</string>
 
+    <string name="downloadFile">Download This File</string>
+    <string name="waitLoadingDownloadFile">Please wait for the file to load to memory</string>
+    <string name="downloadFileSaved">File is saved to Download directory</string>
+    <string name="excludeFilesInFileviewer">This file type is not supported in file viewer. Download it instead from the three dotted menu?</string>
 </resources>