diff --git a/app/src/main/java/ch/dissem/apps/abit/MainActivity.java b/app/src/main/java/ch/dissem/apps/abit/MainActivity.java
index ca8ec07..c6e9296 100644
--- a/app/src/main/java/ch/dissem/apps/abit/MainActivity.java
+++ b/app/src/main/java/ch/dissem/apps/abit/MainActivity.java
@@ -188,6 +188,16 @@ public class MainActivity extends AppCompatActivity
                             .withTag(identity)
             );
         }
+        if (profiles.isEmpty()){
+            // Create an initial identity
+            BitmessageAddress identity = Singleton.getIdentity(this);
+            profiles.add(new ProfileDrawerItem()
+                            .withIcon(new Identicon(identity))
+                            .withName(identity.toString())
+                            .withEmail(identity.getAddress())
+                            .withTag(identity)
+            );
+        }
         profiles.add(new ProfileSettingDrawerItem()
                         .withName("Add Identity")
                         .withDescription("Create new identity")
diff --git a/app/src/main/java/ch/dissem/apps/abit/SubscriptionDetailFragment.java b/app/src/main/java/ch/dissem/apps/abit/SubscriptionDetailFragment.java
index 6d7c3b4..955531f 100644
--- a/app/src/main/java/ch/dissem/apps/abit/SubscriptionDetailFragment.java
+++ b/app/src/main/java/ch/dissem/apps/abit/SubscriptionDetailFragment.java
@@ -100,7 +100,8 @@ public class SubscriptionDetailFragment extends Fragment {
             TextView address = (TextView) rootView.findViewById(R.id.address);
             address.setText(item.getAddress());
             address.setSelected(true);
-            ((TextView) rootView.findViewById(R.id.stream_number)).setText(getActivity().getString(R.string.stream_number, item.getStream()));
+            ((TextView) rootView.findViewById(R.id.stream_number)).setText(getActivity()
+                    .getString(R.string.stream_number, item.getStream()));
             Switch active = (Switch) rootView.findViewById(R.id.active);
             active.setChecked(item.isSubscribed());
             active.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@@ -109,6 +110,14 @@ public class SubscriptionDetailFragment extends Fragment {
                     item.setSubscribed(isChecked);
                 }
             });
+
+            ImageView pubkeyAvailableImg = (ImageView) rootView.findViewById(R.id.pubkey_available);
+            if (item.getPubkey() == null) {
+                pubkeyAvailableImg.setAlpha(0.3f);
+                TextView pubkeyAvailableDesc = (TextView) rootView.findViewById(R.id
+                        .pubkey_available_desc);
+                pubkeyAvailableDesc.setText(R.string.pubkey_not_available);
+            }
         }
 
         return rootView;
diff --git a/app/src/main/java/ch/dissem/apps/abit/repository/AndroidInventory.java b/app/src/main/java/ch/dissem/apps/abit/repository/AndroidInventory.java
index aa20b3e..b7fccaf 100644
--- a/app/src/main/java/ch/dissem/apps/abit/repository/AndroidInventory.java
+++ b/app/src/main/java/ch/dissem/apps/abit/repository/AndroidInventory.java
@@ -33,10 +33,18 @@ import org.slf4j.LoggerFactory;
 
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
+import java.sql.Connection;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 import static ch.dissem.apps.abit.repository.SqlHelper.join;
+import static ch.dissem.bitmessage.utils.UnixTime.MINUTE;
 import static ch.dissem.bitmessage.utils.UnixTime.now;
 
 /**
@@ -55,47 +63,64 @@ public class AndroidInventory implements Inventory {
 
     private final SqlHelper sql;
 
+    private final Map<Long, Map<InventoryVector, Long>> cache = new ConcurrentHashMap<>();
+
     public AndroidInventory(SqlHelper sql) {
         this.sql = sql;
     }
 
     @Override
     public List<InventoryVector> getInventory(long... streams) {
-        return getInventory(false, streams);
+        List<InventoryVector> result = new LinkedList<>();
+        long now = now();
+        for (long stream : streams) {
+            for (Map.Entry<InventoryVector, Long> e : getCache(stream).entrySet()) {
+                if (e.getValue() > now) {
+                    result.add(e.getKey());
+                }
+            }
+        }
+        return result;
     }
 
-    public List<InventoryVector> getInventory(boolean includeExpired, long... streams) {
-        // Define a projection that specifies which columns from the database
-        // you will actually use after this query.
-        String[] projection = {
-                COLUMN_HASH
-        };
+    private Map<InventoryVector, Long> getCache(long stream) {
+        Map<InventoryVector, Long> result = cache.get(stream);
+        if (result == null) {
+            synchronized (cache) {
+                if (cache.get(stream) == null) {
+                    result = new ConcurrentHashMap<>();
+                    cache.put(stream, result);
 
-        SQLiteDatabase db = sql.getReadableDatabase();
-        Cursor c = db.query(
-                TABLE_NAME, projection,
-                (includeExpired ? "" : "expires > " + now() + " AND ") + "stream IN (" + join
-                        (streams) + ")",
-                null, null, null, null
-        );
-        List<InventoryVector> result = new LinkedList<>();
-        try {
-            c.moveToFirst();
-            while (!c.isAfterLast()) {
-                byte[] blob = c.getBlob(c.getColumnIndex(COLUMN_HASH));
-                result.add(new InventoryVector(blob));
-                c.moveToNext();
+                    String[] projection = {
+                            COLUMN_HASH, COLUMN_EXPIRES
+                    };
+
+                    SQLiteDatabase db = sql.getReadableDatabase();
+                    try (Cursor c = db.query(
+                            TABLE_NAME, projection,
+                            "stream = " + stream,
+                            null, null, null, null
+                    )) {
+                        c.moveToFirst();
+                        while (!c.isAfterLast()) {
+                            byte[] blob = c.getBlob(c.getColumnIndex(COLUMN_HASH));
+                            long expires = c.getLong(c.getColumnIndex(COLUMN_EXPIRES));
+                            result.put(new InventoryVector(blob), expires);
+                            c.moveToNext();
+                        }
+                    }
+                    LOG.info("Stream #" + stream + " inventory size: " + result.size());
+                }
             }
-        } finally {
-            c.close();
         }
-        LOG.info("Inventory size: " + result.size());
         return result;
     }
 
     @Override
     public List<InventoryVector> getMissing(List<InventoryVector> offer, long... streams) {
-        offer.removeAll(getInventory(true, streams));
+        for (long stream : streams) {
+            offer.removeAll(getCache(stream).keySet());
+        }
         LOG.info(offer.size() + " objects missing.");
         return offer;
     }
@@ -110,12 +135,11 @@ public class AndroidInventory implements Inventory {
         };
 
         SQLiteDatabase db = sql.getReadableDatabase();
-        Cursor c = db.query(
+        try (Cursor c = db.query(
                 TABLE_NAME, projection,
                 "hash = X'" + vector + "'",
                 null, null, null, null
-        );
-        try {
+        )) {
             c.moveToFirst();
             if (c.isAfterLast()) {
                 LOG.info("Object requested that we don't have. IV: " + vector);
@@ -125,8 +149,6 @@ public class AndroidInventory implements Inventory {
             int version = c.getInt(c.getColumnIndex(COLUMN_VERSION));
             byte[] blob = c.getBlob(c.getColumnIndex(COLUMN_DATA));
             return Factory.getObjectMessage(version, new ByteArrayInputStream(blob), blob.length);
-        } finally {
-            c.close();
         }
     }
 
@@ -150,13 +172,12 @@ public class AndroidInventory implements Inventory {
         }
 
         SQLiteDatabase db = sql.getReadableDatabase();
-        Cursor c = db.query(
+        List<ObjectMessage> result = new LinkedList<>();
+        try (Cursor c = db.query(
                 TABLE_NAME, projection,
                 where.toString(),
                 null, null, null, null
-        );
-        List<ObjectMessage> result = new LinkedList<>();
-        try {
+        )) {
             c.moveToFirst();
             while (!c.isAfterLast()) {
                 int objectVersion = c.getInt(c.getColumnIndex(COLUMN_VERSION));
@@ -165,8 +186,6 @@ public class AndroidInventory implements Inventory {
                         blob.length));
                 c.moveToNext();
             }
-        } finally {
-            c.close();
         }
         return result;
     }
@@ -174,6 +193,10 @@ public class AndroidInventory implements Inventory {
     @Override
     public void storeObject(ObjectMessage object) {
         InventoryVector iv = object.getInventoryVector();
+
+        if (getCache(object.getStream()).containsKey(iv))
+            return;
+
         LOG.trace("Storing object " + iv);
 
         try {
@@ -188,6 +211,8 @@ public class AndroidInventory implements Inventory {
             values.put(COLUMN_VERSION, object.getVersion());
 
             db.insertOrThrow(TABLE_NAME, null, values);
+
+            getCache(object.getStream()).put(iv, object.getExpiresTime());
         } catch (SQLiteConstraintException e) {
             LOG.trace(e.getMessage(), e);
         } catch (IOException e) {
@@ -197,22 +222,22 @@ public class AndroidInventory implements Inventory {
 
     @Override
     public boolean contains(ObjectMessage object) {
-        SQLiteDatabase db = sql.getReadableDatabase();
-        Cursor c = db.query(
-                TABLE_NAME, new String[]{COLUMN_STREAM},
-                "hash = X'" + object.getInventoryVector() + "'",
-                null, null, null, null
-        );
-        try {
-            return c.getCount() > 0;
-        } finally {
-            c.close();
-        }
+        return getCache(object.getStream()).keySet().contains(object.getInventoryVector());
     }
 
     @Override
     public void cleanup() {
+        long fiveMinutesAgo = now() - 5 * MINUTE;
         SQLiteDatabase db = sql.getWritableDatabase();
-        db.delete(TABLE_NAME, "expires < " + (now() - 300), null);
+        db.delete(TABLE_NAME, "expires < " + fiveMinutesAgo, null);
+
+        for (Map<InventoryVector, Long> c : cache.values()) {
+            Iterator<Map.Entry<InventoryVector, Long>> iterator = c.entrySet().iterator();
+            while (iterator.hasNext()) {
+                if (iterator.next().getValue() < fiveMinutesAgo) {
+                    iterator.remove();
+                }
+            }
+        }
     }
 }
diff --git a/app/src/main/java/ch/dissem/apps/abit/service/BitmessageService.java b/app/src/main/java/ch/dissem/apps/abit/service/BitmessageService.java
index b5c18f6..691db2c 100644
--- a/app/src/main/java/ch/dissem/apps/abit/service/BitmessageService.java
+++ b/app/src/main/java/ch/dissem/apps/abit/service/BitmessageService.java
@@ -56,7 +56,7 @@ public class BitmessageService extends Service {
     private static Messenger messenger;
 
     public static boolean isRunning() {
-        return running;
+        return running && bmc.isRunning();
     }
 
     @Override
@@ -102,8 +102,6 @@ public class BitmessageService extends Service {
             switch (msg.what) {
                 case MSG_CREATE_IDENTITY: {
                     BitmessageAddress identity = bmc.createIdentity(false);
-                    identity.setAlias(service.get().getString(R.string.alias_default_identity));
-                    bmc.addresses().save(identity);
                     if (msg.replyTo != null) {
                         try {
                             Message message = Message.obtain(this, MSG_CREATE_IDENTITY);
diff --git a/app/src/main/java/ch/dissem/apps/abit/service/Singleton.java b/app/src/main/java/ch/dissem/apps/abit/service/Singleton.java
index 9c60ecf..50c95da 100644
--- a/app/src/main/java/ch/dissem/apps/abit/service/Singleton.java
+++ b/app/src/main/java/ch/dissem/apps/abit/service/Singleton.java
@@ -4,6 +4,7 @@ import android.content.Context;
 
 import java.util.List;
 
+import ch.dissem.apps.abit.R;
 import ch.dissem.apps.abit.adapter.AndroidCryptography;
 import ch.dissem.apps.abit.adapter.SwitchingProofOfWorkEngine;
 import ch.dissem.apps.abit.listener.MessageListener;
@@ -92,10 +93,15 @@ public class Singleton {
         if (identity == null) {
             synchronized (Singleton.class) {
                 if (identity == null) {
-                    List<BitmessageAddress> identities = getBitmessageContext(ctx).addresses()
+                    BitmessageContext bmc = getBitmessageContext(ctx);
+                    List<BitmessageAddress> identities = bmc.addresses()
                             .getIdentities();
                     if (identities.size() > 0) {
                         identity = identities.get(0);
+                    } else {
+                        identity = bmc.createIdentity(false);
+                        identity.setAlias(ctx.getString(R.string.alias_default_identity));
+                        bmc.addresses().save(identity);
                     }
                 }
             }
diff --git a/app/src/main/res/drawable/public_key.xml b/app/src/main/res/drawable/public_key.xml
new file mode 100644
index 0000000..d3cea1a
--- /dev/null
+++ b/app/src/main/res/drawable/public_key.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+        android:height="24dp"
+        android:width="24dp"
+        android:viewportWidth="24"
+        android:viewportHeight="24">
+    <path android:fillColor="#000" android:pathData="M18,8A2,2 0 0,1 20,10V20A2,2 0 0,1 18,22H6C4.89,22 4,21.1 4,20V10A2,2 0 0,1 6,8H15V6A3,3 0 0,0 12,3A3,3 0 0,0 9,6H7A5,5 0 0,1 12,1A5,5 0 0,1 17,6V8H18M12,17A2,2 0 0,0 14,15A2,2 0 0,0 12,13A2,2 0 0,0 10,15A2,2 0 0,0 12,17Z" />
+</vector>
\ No newline at end of file
diff --git a/app/src/main/res/layout/fragment_contact_detail.xml b/app/src/main/res/layout/fragment_contact_detail.xml
index 4aa33dd..f8b4bda 100644
--- a/app/src/main/res/layout/fragment_contact_detail.xml
+++ b/app/src/main/res/layout/fragment_contact_detail.xml
@@ -16,65 +16,90 @@
   -->
 
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+                xmlns:tools="http://schemas.android.com/tools"
                 android:layout_width="match_parent"
                 android:layout_height="match_parent">
 
     <ImageView
-            android:id="@+id/avatar"
-            android:layout_width="40dp"
-            android:layout_height="40dp"
-            android:layout_alignParentTop="true"
-            android:layout_alignParentLeft="true"
-            android:layout_alignParentStart="true"
-            android:src="@color/colorAccent"
-            android:layout_margin="16dp"/>
+        android:id="@+id/avatar"
+        android:layout_width="40dp"
+        android:layout_height="40dp"
+        android:layout_alignParentStart="true"
+        android:layout_alignParentTop="true"
+        android:layout_margin="16dp"
+        android:src="@color/colorAccent"
+        tools:ignore="ContentDescription"/>
 
     <EditText
-            android:id="@+id/name"
-            android:layout_width="0dp"
-            android:layout_height="wrap_content"
-            android:text="Name"
-            android:layout_alignTop="@+id/avatar"
-            android:layout_toRightOf="@+id/avatar"
-            android:layout_toEndOf="@+id/avatar"
-            android:layout_marginRight="16dp"
-            android:layout_marginEnd="16dp"
-            android:layout_alignParentRight="true"
-            android:layout_alignParentEnd="true"/>
+        android:id="@+id/name"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_alignParentEnd="true"
+        android:layout_alignTop="@+id/avatar"
+        android:layout_marginEnd="16dp"
+        android:layout_toEndOf="@+id/avatar"
+        android:text=""
+        android:inputType="textPersonName"
+        tools:ignore="LabelFor"/>
 
     <TextView
-            android:id="@+id/address"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:text="Address"
-            android:lines="1"
-            android:textAppearance="?android:attr/textAppearanceSmall"
-            android:layout_below="@+id/avatar"
-            android:paddingLeft="16dp"
-            android:paddingRight="16dp"
-            android:textStyle="bold"
-            />
+        android:id="@+id/address"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_below="@+id/avatar"
+        android:lines="1"
+        android:paddingLeft="16dp"
+        android:paddingRight="16dp"
+        android:text="BM-XyYxXyYxXyYxXyYxXyYx"
+        android:textAppearance="?android:attr/textAppearanceSmall"
+        android:textStyle="bold"
+        tools:ignore="HardcodedText"/>
 
     <TextView
-            android:id="@+id/stream_number"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:text="Stream #"
-            android:lines="1"
-            android:ellipsize="end"
-            android:textAppearance="?android:attr/textAppearanceSmall"
-            android:paddingLeft="16dp"
-            android:paddingRight="16dp"
-            android:layout_below="@+id/address"/>
+        android:id="@+id/stream_number"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_below="@+id/address"
+        android:ellipsize="end"
+        android:lines="1"
+        android:paddingLeft="16dp"
+        android:paddingRight="16dp"
+        android:text="Stream #"
+        android:textAppearance="?android:attr/textAppearanceSmall"
+        tools:ignore="HardcodedText"/>
 
     <Switch
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:text="@string/subscribed"
-            android:id="@+id/active"
-            android:paddingTop="16dp"
-            android:paddingLeft="16dp"
-            android:paddingRight="16dp"
-            android:layout_below="@+id/stream_number"/>
+        android:id="@+id/active"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_below="@+id/stream_number"
+        android:paddingLeft="16dp"
+        android:paddingRight="16dp"
+        android:paddingTop="16dp"
+        android:text="@string/subscribed"/>
+
+    <ImageView
+        android:id="@+id/pubkey_available"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_alignParentStart="true"
+        android:layout_below="@+id/active"
+        android:paddingStart="16dp"
+        android:paddingEnd="4dp"
+        android:paddingTop="16dp"
+        android:src="@drawable/public_key"
+        tools:ignore="ContentDescription"/>
+
+    <TextView
+        android:id="@+id/pubkey_available_desc"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:paddingStart="0dp"
+        android:paddingEnd="16dp"
+        android:layout_alignBottom="@id/pubkey_available"
+        android:layout_toEndOf="@id/pubkey_available"
+        android:layout_alignParentEnd="true"
+        android:text="@string/pubkey_available"
+        android:textAppearance="?android:attr/textAppearanceSmall"/>
 
 </RelativeLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values-de/strings.xml b/app/src/main/res/values-de/strings.xml
index 279491a..bc0d062 100644
--- a/app/src/main/res/values-de/strings.xml
+++ b/app/src/main/res/values-de/strings.xml
@@ -56,4 +56,6 @@
     <string name="alias_default_identity">Ich</string>
     <string name="title_activity_status">Debugging</string>
     <string name="status_summary">Technische Infos</string>
+    <string name="pubkey_available">Öffentlicher Schlüssel verfügbar</string>
+    <string name="pubkey_not_available">Öffentlicher Schlüssel noch nicht verfügbar</string>
 </resources>
\ 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 83c5d60..7a4e21c 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -59,4 +59,6 @@
     <string name="status">Debugging</string>
     <string name="status_summary">Technical information</string>
     <string name="alias_default_identity">Me</string>
+    <string name="pubkey_available">Public key available</string>
+    <string name="pubkey_not_available">Public key not yet available</string>
 </resources>