diff --git a/app/src/main/java/im/status/applet_installer_test/appletinstaller/CardChannel.java b/app/src/main/java/im/status/applet_installer_test/appletinstaller/CardChannel.java
new file mode 100644
index 0000000..ad8db5e
--- /dev/null
+++ b/app/src/main/java/im/status/applet_installer_test/appletinstaller/CardChannel.java
@@ -0,0 +1,22 @@
+package im.status.applet_installer_test.appletinstaller;
+
+import android.nfc.tech.IsoDep;
+
+import java.io.IOException;
+
+import im.status.applet_installer_test.appletinstaller.CardManager;
+
+public class CardChannel implements Channel {
+    private IsoDep isoDep;
+
+    public CardChannel(IsoDep isoDep) {
+        this.isoDep = isoDep;
+    }
+
+    public byte[] transceive(byte[] data) throws IOException {
+        Logger.log(String.format("COMMAND %s %n", HexUtils.byteArrayToHexString(data)));
+        byte[] resp = this.isoDep.transceive(data);
+        Logger.log(String.format("RESPONSE %s %n", HexUtils.byteArrayToHexString(resp)));
+        return resp;
+    }
+}
diff --git a/app/src/main/java/im/status/applet_installer_test/appletinstaller/CardManager.java b/app/src/main/java/im/status/applet_installer_test/appletinstaller/CardManager.java
new file mode 100644
index 0000000..47c3fa5
--- /dev/null
+++ b/app/src/main/java/im/status/applet_installer_test/appletinstaller/CardManager.java
@@ -0,0 +1,26 @@
+package im.status.applet_installer_test.appletinstaller;
+
+import android.nfc.Tag;
+import android.nfc.tech.IsoDep;
+
+import java.io.IOException;
+
+public class CardManager {
+    private Tag tag;
+    private IsoDep isoDep;
+
+    public CardManager(Tag tag) {
+        this.tag = tag;
+    }
+
+    public void connect() throws IOException {
+        this.isoDep = IsoDep.get(tag);
+        this.isoDep.connect();
+    }
+
+    public void install() throws IOException, APDUException {
+        CardChannel ch = new CardChannel(this.isoDep);
+        Installer installer = new Installer(ch);
+        installer.start();
+    }
+}
diff --git a/app/src/main/java/im/status/applet_installer_test/appletinstaller/Channel.java b/app/src/main/java/im/status/applet_installer_test/appletinstaller/Channel.java
new file mode 100644
index 0000000..ee049bb
--- /dev/null
+++ b/app/src/main/java/im/status/applet_installer_test/appletinstaller/Channel.java
@@ -0,0 +1,7 @@
+package im.status.applet_installer_test.appletinstaller;
+
+import java.io.IOException;
+
+public interface Channel {
+    byte[] transceive(byte[] data) throws IOException;
+}
diff --git a/app/src/main/java/im/status/applet_installer_test/appletinstaller/Crypto.java b/app/src/main/java/im/status/applet_installer_test/appletinstaller/Crypto.java
index cfd1ba1..6c5fb36 100644
--- a/app/src/main/java/im/status/applet_installer_test/appletinstaller/Crypto.java
+++ b/app/src/main/java/im/status/applet_installer_test/appletinstaller/Crypto.java
@@ -15,7 +15,6 @@ import javax.crypto.spec.SecretKeySpec;
 
 
 public class Crypto {
-
     public static final byte[] NullBytes8 = new byte[]{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
 
     public static byte[] deriveKey(byte[] cardKey, byte[] seq, byte[] purposeData) {
diff --git a/app/src/main/java/im/status/applet_installer_test/appletinstaller/Installer.java b/app/src/main/java/im/status/applet_installer_test/appletinstaller/Installer.java
new file mode 100644
index 0000000..950c828
--- /dev/null
+++ b/app/src/main/java/im/status/applet_installer_test/appletinstaller/Installer.java
@@ -0,0 +1,36 @@
+package im.status.applet_installer_test.appletinstaller;
+
+import java.io.IOException;
+import java.security.SecureRandom;
+
+import im.status.applet_installer_test.appletinstaller.apducommands.InitializeUpdate;
+
+public class Installer {
+    private Channel channel;
+
+    static final byte[] cardKeyData = HexUtils.hexStringToByteArray("404142434445464748494a4b4c4d4e4f");
+
+    private Keys cardKeys;
+
+    public Installer(Channel channel) {
+        this.channel = channel;
+        this.cardKeys = new Keys(cardKeyData, cardKeyData);
+    }
+
+    public void start() throws IOException, APDUException {
+        SecureRandom random = new SecureRandom();
+        byte hostChallenge[] = new byte[8];
+        random.nextBytes(hostChallenge);
+        InitializeUpdate init = new InitializeUpdate(hostChallenge);
+        byte[] data = init.getCommand().serialize();
+
+        // get data
+        //byte[] data = new byte[]{(byte) 0x80, (byte) 0xCA, 0x00, (byte) 0x66};
+
+        byte[] respData = this.channel.transceive(data);
+        APDUResponse resp = new APDUResponse(respData);
+        Logger.log(respData);
+
+        Keys keys = init.verifyResponse(this.cardKeys, resp);
+    }
+}
diff --git a/app/src/main/java/im/status/applet_installer_test/appletinstaller/Keys.java b/app/src/main/java/im/status/applet_installer_test/appletinstaller/Keys.java
new file mode 100644
index 0000000..c6f9e76
--- /dev/null
+++ b/app/src/main/java/im/status/applet_installer_test/appletinstaller/Keys.java
@@ -0,0 +1,19 @@
+package im.status.applet_installer_test.appletinstaller;
+
+public class Keys {
+    public byte[] encKeyData;
+    public byte[] macKeyData;
+
+    public Keys(byte[] encKeyData, byte[] macKeyData) {
+        this.encKeyData = encKeyData;
+        this.macKeyData = macKeyData;
+    }
+
+    public byte[] getEncKeyData() {
+        return encKeyData;
+    }
+
+    public byte[] getMacKeyData() {
+        return macKeyData;
+    }
+}
diff --git a/app/src/main/java/im/status/applet_installer_test/appletinstaller/Logger.java b/app/src/main/java/im/status/applet_installer_test/appletinstaller/Logger.java
new file mode 100644
index 0000000..2b5d7f0
--- /dev/null
+++ b/app/src/main/java/im/status/applet_installer_test/appletinstaller/Logger.java
@@ -0,0 +1,13 @@
+package im.status.applet_installer_test.appletinstaller;
+
+import android.util.Log;
+
+public class Logger {
+    public static void log(String m) {
+        Log.d("installer-debug", m);
+    }
+
+    public static void log(byte[] m) {
+        Log.d("installer-debug", HexUtils.byteArrayToHexString(m));
+    }
+}
diff --git a/app/src/main/java/im/status/applet_installer_test/appletinstaller/apducommands/InitializeUpdate.java b/app/src/main/java/im/status/applet_installer_test/appletinstaller/apducommands/InitializeUpdate.java
index 7361c08..6879ae0 100644
--- a/app/src/main/java/im/status/applet_installer_test/appletinstaller/apducommands/InitializeUpdate.java
+++ b/app/src/main/java/im/status/applet_installer_test/appletinstaller/apducommands/InitializeUpdate.java
@@ -7,6 +7,8 @@ import im.status.applet_installer_test.appletinstaller.APDUException;
 import im.status.applet_installer_test.appletinstaller.APDUResponse;
 import im.status.applet_installer_test.appletinstaller.Crypto;
 import im.status.applet_installer_test.appletinstaller.HexUtils;
+import im.status.applet_installer_test.appletinstaller.Keys;
+import im.status.applet_installer_test.appletinstaller.Logger;
 
 public class InitializeUpdate {
     public static final int CLA = 0x80;
@@ -36,7 +38,7 @@ public class InitializeUpdate {
         return challenge;
     }
 
-    public boolean validateResponse(byte[] encKeyData, APDUResponse resp) throws APDUException {
+    public Keys verifyResponse(Keys cardKeys, APDUResponse resp) throws APDUException {
         if (resp.getSw() == APDUResponse.SW_SECURITY_CONDITION_NOT_SATISFIED) {
             throw new APDUException(resp.getSw(), "security confition not satisfied");
         }
@@ -57,9 +59,17 @@ public class InitializeUpdate {
         byte[] cardCryptogram = new byte[8];
         System.arraycopy(data, 20, cardCryptogram, 0, 8);
 
-        return Crypto.verifyCryptogram(encKeyData, this.hostChallenge, cardChallenge, cardCryptogram);
+        byte[] seq = new byte[2];
+        System.arraycopy(data, 12, seq, 0, 2);
 
-        //System.out.printf("key data: %s, %n", HexUtils.byteArrayToHexString(keyData));
+        byte[] sessionEncKey = Crypto.deriveKey(cardKeys.getEncKeyData(), seq, DERIVATION_PURPOSE_ENC);
+        byte[] sessionMacKey = Crypto.deriveKey(cardKeys.getMacKeyData(), seq, DERIVATION_PURPOSE_MAC);
 
+        Keys sessionKeys = new Keys(sessionEncKey, sessionMacKey);
+
+        boolean x = Crypto.verifyCryptogram(sessionKeys.getEncKeyData(), this.hostChallenge, cardChallenge, cardCryptogram);
+        Logger.log("VERIFIED: " + x);
+
+        return sessionKeys;
     }
 }