diff --git a/app/build.gradle b/app/build.gradle
index 90f582a051..f91af6af43 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -53,6 +53,7 @@ dependencies {
     implementation 'androidx.appcompat:appcompat:1.1.0-alpha01'
     implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
     implementation "androidx.lifecycle:lifecycle-extensions:$lifecycle_version"
+    implementation 'androidx.biometric:biometric:1.0.0-alpha03'
     implementation 'com.google.android.material:material:1.1.0-alpha02'
     implementation 'com.google.dagger:dagger:2.16'
     implementation 'com.google.zxing:core:3.3.3'
diff --git a/app/src/main/java/com/tangem/presentation/activity/PinRequestActivity.kt b/app/src/main/java/com/tangem/presentation/activity/PinRequestActivity.kt
index 576ace6402..23ab30cf58 100644
--- a/app/src/main/java/com/tangem/presentation/activity/PinRequestActivity.kt
+++ b/app/src/main/java/com/tangem/presentation/activity/PinRequestActivity.kt
@@ -173,8 +173,7 @@ class PinRequestActivity : AppCompatActivity(), NfcAdapter.ReaderCallback, Finge
 
     override fun onPause() {
         super.onPause()
-        if (fingerprintHelper != null)
-            fingerprintHelper!!.cancel()
+        fingerprintHelper?.cancel()
 
         if (startFingerprintReaderTask != null) {
             startFingerprintReaderTask!!.cancel(true)
@@ -184,8 +183,7 @@ class PinRequestActivity : AppCompatActivity(), NfcAdapter.ReaderCallback, Finge
 
     override fun onStop() {
         super.onStop()
-        if (fingerprintHelper != null)
-            fingerprintHelper!!.cancel()
+        fingerprintHelper?.cancel()
 
         if (startFingerprintReaderTask != null) {
             startFingerprintReaderTask!!.cancel(true)
@@ -214,7 +212,7 @@ class PinRequestActivity : AppCompatActivity(), NfcAdapter.ReaderCallback, Finge
 
     @TargetApi(Build.VERSION_CODES.M)
     override fun authenticationSucceeded(result: FingerprintManager.AuthenticationResult) {
-        LOG.i(TAG,"Authentication succeeded!")
+        LOG.i(TAG, "Authentication succeeded!")
         val cipher = result.cryptoObject.cipher
 
         if (mode == Mode.RequestNewPIN || mode == Mode.ConfirmNewPIN) {
@@ -242,34 +240,33 @@ class PinRequestActivity : AppCompatActivity(), NfcAdapter.ReaderCallback, Finge
         finish()
     }
 
-    @SuppressLint("SetTextI18n")
     private fun buttonClick(button: Button) {
-        tvPin!!.text = tvPin!!.text.toString() + button.text as String
+        tvPin.text = tvPin.text.toString() + button.text.toString()
     }
 
     @SuppressLint("NewApi")
     private fun testFingerPrintSettings(): Boolean {
-        LOG.i(TAG,"Testing Fingerprint Settings")
+        LOG.i(TAG, "Testing Fingerprint Settings")
 
         val keyguardManager = getSystemService(Context.KEYGUARD_SERVICE) as KeyguardManager
         fingerprintManager = getSystemService(Context.FINGERPRINT_SERVICE) as FingerprintManager
 
         if (!keyguardManager.isKeyguardSecure) {
-            LOG.i(TAG,"User hasn't enabled Lock Screen")
+            LOG.i(TAG, "User hasn't enabled Lock Screen")
             return false
         }
 
         if (ActivityCompat.checkSelfPermission(this, Manifest.permission.USE_FINGERPRINT) != PackageManager.PERMISSION_GRANTED) {
-            LOG.i(TAG,"User hasn't granted permission to use Fingerprint")
+            LOG.i(TAG, "User hasn't granted permission to use Fingerprint")
             return false
         }
 
         if (!fingerprintManager!!.hasEnrolledFingerprints()) {
-            LOG.i(TAG,"User hasn't registered any fingerprints")
+            LOG.i(TAG, "User hasn't registered any fingerprints")
             return false
         }
 
-        LOG.i(TAG,"Fingerprint authentication is set.\n")
+        LOG.i(TAG, "Fingerprint authentication is set.\n")
 
         return true
     }
diff --git a/app/src/main/java/com/tangem/presentation/activity/PrepareTransactionActivity.kt b/app/src/main/java/com/tangem/presentation/activity/PrepareTransactionActivity.kt
index 4da817a270..2a5cd99068 100644
--- a/app/src/main/java/com/tangem/presentation/activity/PrepareTransactionActivity.kt
+++ b/app/src/main/java/com/tangem/presentation/activity/PrepareTransactionActivity.kt
@@ -11,6 +11,7 @@ import android.text.Html
 import android.view.View
 import android.view.inputmethod.EditorInfo
 import android.view.inputmethod.InputMethodManager
+import android.widget.Toast
 import androidx.appcompat.app.AppCompatActivity
 import com.tangem.App
 import com.tangem.Constant
@@ -20,6 +21,7 @@ import com.tangem.domain.wallet.CoinEngineFactory
 import com.tangem.domain.wallet.TangemContext
 import com.tangem.tangemcard.android.nfc.NfcLifecycleObserver
 import com.tangem.tangemcard.android.reader.NfcManager
+import com.tangem.util.UtilHelper
 import com.tangem.wallet.R
 import kotlinx.android.synthetic.main.activity_prepare_transaction.*
 import java.io.IOException
@@ -89,8 +91,12 @@ class PrepareTransactionActivity : AppCompatActivity(), NfcAdapter.ReaderCallbac
         }
 
         btnVerify.setOnClickListener {
-            val engine1 = CoinEngineFactory.create(ctx)
+            if (!UtilHelper.isOnline(this)) {
+                Toast.makeText(this, R.string.no_connection, Toast.LENGTH_LONG).show()
+                return@setOnClickListener
+            }
 
+            val engine1 = CoinEngineFactory.create(ctx)
             val strAmount: String = etAmount.text.toString().replace(",", ".")
             val amount = engine1!!.convertToAmount(etAmount.text.toString(), tvCurrency.text.toString())
 
diff --git a/app/src/main/java/com/tangem/presentation/dialog/ShowQRCodeDialog.java b/app/src/main/java/com/tangem/presentation/dialog/ShowQRCodeDialog.java
index a3b588f885..475986f0b9 100644
--- a/app/src/main/java/com/tangem/presentation/dialog/ShowQRCodeDialog.java
+++ b/app/src/main/java/com/tangem/presentation/dialog/ShowQRCodeDialog.java
@@ -1,6 +1,5 @@
 package com.tangem.presentation.dialog;
 
-import android.app.Activity;
 import android.app.AlertDialog;
 import android.app.Dialog;
 import android.content.DialogInterface;
diff --git a/app/src/main/java/com/tangem/util/UtilHelper.kt b/app/src/main/java/com/tangem/util/UtilHelper.kt
index 63daab7ea5..060a82cf76 100644
--- a/app/src/main/java/com/tangem/util/UtilHelper.kt
+++ b/app/src/main/java/com/tangem/util/UtilHelper.kt
@@ -1,6 +1,5 @@
 package com.tangem.util
 
-import android.app.Activity
 import android.content.Context
 import android.graphics.Bitmap
 import android.graphics.Color
diff --git a/app/src/main/res/layout/activity_prepare_transaction.xml b/app/src/main/res/layout/activity_prepare_transaction.xml
index b5059e66f2..1d4951d4c3 100644
--- a/app/src/main/res/layout/activity_prepare_transaction.xml
+++ b/app/src/main/res/layout/activity_prepare_transaction.xml
@@ -1,26 +1,26 @@
 <?xml version="1.0" encoding="utf-8"?>
-<androidx.constraintlayout.widget.ConstraintLayout
-    xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    tools:context="com.tangem.presentation.activity.PrepareTransactionActivity">
+    tools:context="com.tangem.presentation.activity.PrepareTransactionActivity"
+    tools:ignore="contentDescription">
 
     <TextView
         android:id="@+id/textView"
         android:layout_width="0dp"
         android:layout_height="wrap_content"
         android:fontFamily="@font/maax"
-        android:paddingBottom="8dp"
         android:paddingTop="8dp"
+        android:paddingBottom="8dp"
         android:text="@string/send_transaction"
         android:textAlignment="center"
         android:textColor="@color/primary"
         android:textSize="@dimen/text_size_large"
         app:layout_constraintLeft_toLeftOf="parent"
         app:layout_constraintRight_toRightOf="parent"
-        app:layout_constraintTop_toTopOf="parent"/>
+        app:layout_constraintTop_toTopOf="parent" />
 
     <LinearLayout
         android:id="@+id/llFrom"
@@ -28,10 +28,10 @@
         android:layout_height="wrap_content"
         android:background="@color/btn_light"
         android:orientation="vertical"
-        android:paddingBottom="24dp"
-        android:paddingEnd="8dp"
         android:paddingStart="8dp"
         android:paddingTop="24dp"
+        android:paddingEnd="8dp"
+        android:paddingBottom="24dp"
         app:layout_constraintHorizontal_bias="0.0"
         app:layout_constraintLeft_toLeftOf="parent"
         app:layout_constraintRight_toRightOf="parent"
@@ -45,7 +45,7 @@
             android:fontFamily="@font/maax"
             android:text="@string/from_banknote"
             android:textColor="@color/primary"
-            android:textSize="@dimen/text_size_medium"/>
+            android:textSize="@dimen/text_size_medium" />
 
         <TextView
             android:id="@+id/tvCardID"
@@ -57,7 +57,7 @@
             android:textColor="@color/black"
             android:textSize="@dimen/text_size_medium"
             android:textStyle="bold"
-            tools:text="BB00 0000 1210 0233"/>
+            tools:text="BB00 0000 1210 0233" />
 
         <TextView
             android:layout_width="wrap_content"
@@ -67,7 +67,7 @@
             android:fontFamily="@font/maax"
             android:text="@string/with_balance"
             android:textColor="@color/primary"
-            android:textSize="@dimen/text_size_medium"/>
+            android:textSize="@dimen/text_size_medium" />
 
         <LinearLayout
             android:layout_width="wrap_content"
@@ -78,14 +78,14 @@
                 android:id="@+id/tvBalance"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
-                android:layout_marginBottom="2dp"
                 android:layout_marginStart="16dp"
                 android:layout_marginTop="4dp"
+                android:layout_marginBottom="2dp"
                 android:fontFamily="@font/maax"
                 android:textColor="@color/black"
                 android:textSize="@dimen/text_size_medium"
                 android:textStyle="bold"
-                tools:text="4.51735 Btc"/>
+                tools:text="4.51735 Btc" />
 
         </LinearLayout>
 
@@ -119,7 +119,7 @@
                 android:textSize="@dimen/text_size_medium"
                 app:layout_constraintBottom_toBottomOf="parent"
                 app:layout_constraintLeft_toLeftOf="parent"
-                app:layout_constraintTop_toTopOf="parent"/>
+                app:layout_constraintTop_toTopOf="parent" />
 
             <ImageView
                 android:id="@+id/ivCamera"
@@ -129,7 +129,7 @@
                 android:src="@drawable/qr_scan"
                 app:layout_constraintBottom_toBottomOf="parent"
                 app:layout_constraintRight_toRightOf="parent"
-                app:layout_constraintTop_toTopOf="parent"/>
+                app:layout_constraintTop_toTopOf="parent" />
 
         </LinearLayout>
 
@@ -137,12 +137,12 @@
             android:id="@+id/etWallet"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
-            android:layout_marginEnd="8dp"
             android:layout_marginStart="8dp"
+            android:layout_marginEnd="8dp"
             android:fontFamily="@font/maax"
             android:hint="@string/enter_wallet_address"
-            android:inputType="text|textMultiLine|textNoSuggestions"
             android:imeOptions="actionNext"
+            android:inputType="text|textMultiLine|textNoSuggestions"
             android:padding="12dp"
             android:singleLine="false"
             android:textColor="@color/colorPrimaryDark"
@@ -150,7 +150,7 @@
             android:textSize="@dimen/text_size_medium"
             app:layout_constraintLeft_toLeftOf="parent"
             app:layout_constraintRight_toLeftOf="@+id/ivCamera"
-            tools:layout_editor_absoluteY="2dp"/>
+            tools:layout_editor_absoluteY="2dp" />
 
         <androidx.constraintlayout.widget.ConstraintLayout
             android:layout_width="match_parent"
@@ -160,16 +160,16 @@
                 android:id="@+id/textView3"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
-                android:layout_marginBottom="8dp"
                 android:layout_marginStart="7dp"
                 android:layout_marginTop="24dp"
+                android:layout_marginBottom="8dp"
                 android:fontFamily="@font/maax"
                 android:text="@string/amount"
                 android:textColor="@color/primary"
                 android:textSize="@dimen/text_size_medium"
                 app:layout_constraintBottom_toBottomOf="parent"
                 app:layout_constraintLeft_toLeftOf="parent"
-                app:layout_constraintTop_toTopOf="parent"/>
+                app:layout_constraintTop_toTopOf="parent" />
 
         </androidx.constraintlayout.widget.ConstraintLayout>
 
@@ -194,14 +194,14 @@
                 app:layout_constraintBottom_toBottomOf="parent"
                 app:layout_constraintLeft_toLeftOf="parent"
                 app:layout_constraintTop_toTopOf="parent"
-                app:layout_constraintWidth_min="150dp"/>
+                app:layout_constraintWidth_min="150dp" />
 
             <TextView
                 android:id="@+id/tvCurrency"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
-                android:layout_marginBottom="8dp"
                 android:layout_marginStart="8dp"
+                android:layout_marginBottom="8dp"
                 android:fontFamily="@font/maax"
                 android:text="@string/m_btc"
                 android:textColor="@color/primary"