diff --git a/app/src/main/java/io/heckel/ntfy/ui/DetailActivity.kt b/app/src/main/java/io/heckel/ntfy/ui/DetailActivity.kt
index 01e82ad..9bf7b2f 100644
--- a/app/src/main/java/io/heckel/ntfy/ui/DetailActivity.kt
+++ b/app/src/main/java/io/heckel/ntfy/ui/DetailActivity.kt
@@ -115,6 +115,10 @@ class DetailActivity : AppCompatActivity(), ActionMode.Callback {
                 onRefreshClick()
                 true
             }
+            R.id.detail_menu_clear -> {
+                onClearClick()
+                true
+            }
             R.id.detail_menu_unsubscribe -> {
                 onDeleteClick()
                 true
@@ -123,7 +127,22 @@ class DetailActivity : AppCompatActivity(), ActionMode.Callback {
         }
     }
 
+    private fun onTestClick() {
+        Log.d(TAG, "Sending test notification to ${topicShortUrl(subscriptionBaseUrl, subscriptionTopic)}")
+
+        val message = getString(R.string.detail_test_message, Date().toString())
+        val successFn = { _: String -> }
+        val failureFn = { error: VolleyError ->
+            Toast
+                .makeText(this, getString(R.string.detail_test_message_error, error.message), Toast.LENGTH_LONG)
+                .show()
+        }
+        api.publish(subscriptionBaseUrl, subscriptionTopic, message, successFn, failureFn)
+    }
+
     private fun onRefreshClick() {
+        Log.d(TAG, "Fetching cached notifications for ${topicShortUrl(subscriptionBaseUrl, subscriptionTopic)}")
+
         val activity = this
         val successFn = { notifications: List<Notification> ->
             lifecycleScope.launch(Dispatchers.IO) {
@@ -147,15 +166,16 @@ class DetailActivity : AppCompatActivity(), ActionMode.Callback {
         api.poll(subscriptionId, subscriptionBaseUrl, subscriptionTopic, successFn, failureFn)
     }
 
-    private fun onTestClick() {
-        val message = getString(R.string.detail_test_message, Date().toString())
-        val successFn = { _: String -> }
-        val failureFn = { error: VolleyError ->
-            Toast
-                .makeText(this, getString(R.string.detail_test_message_error, error.message), Toast.LENGTH_LONG)
-                .show()
-        }
-        api.publish(subscriptionBaseUrl, subscriptionTopic, message, successFn, failureFn)
+    private fun onClearClick() {
+        val builder = AlertDialog.Builder(this)
+        builder
+            .setMessage(R.string.detail_clear_dialog_message)
+            .setPositiveButton(R.string.detail_clear_dialog_permanently_delete) { _, _ ->
+                viewModel.removeAll(subscriptionId)
+            }
+            .setNegativeButton(R.string.detail_clear_dialog_cancel) { _, _ -> /* Do nothing */ }
+            .create()
+            .show()
     }
 
     private fun onDeleteClick() {
diff --git a/app/src/main/java/io/heckel/ntfy/ui/MainActivity.kt b/app/src/main/java/io/heckel/ntfy/ui/MainActivity.kt
index 487db92..5efe727 100644
--- a/app/src/main/java/io/heckel/ntfy/ui/MainActivity.kt
+++ b/app/src/main/java/io/heckel/ntfy/ui/MainActivity.kt
@@ -8,15 +8,21 @@ import android.net.Uri
 import android.os.Bundle
 import android.util.Log
 import android.view.*
+import android.widget.Toast
 import androidx.activity.viewModels
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.content.ContextCompat
+import androidx.lifecycle.lifecycleScope
 import androidx.recyclerview.widget.RecyclerView
 import com.google.firebase.messaging.FirebaseMessaging
 import io.heckel.ntfy.R
 import io.heckel.ntfy.app.Application
+import io.heckel.ntfy.data.Notification
 import io.heckel.ntfy.data.Subscription
 import io.heckel.ntfy.data.topicShortUrl
+import io.heckel.ntfy.msg.ApiService
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
 import java.util.*
 import kotlin.random.Random
 
@@ -24,15 +30,20 @@ class MainActivity : AppCompatActivity(), ActionMode.Callback {
     private val viewModel by viewModels<SubscriptionsViewModel> {
         SubscriptionsViewModelFactory((application as Application).repository)
     }
+    private val repository by lazy { (application as Application).repository }
     private lateinit var mainList: RecyclerView
     private lateinit var adapter: MainAdapter
     private lateinit var fab: View
     private var actionMode: ActionMode? = null
+    private lateinit var api: ApiService // Context-dependent
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.main_activity)
 
+        // Dependencies that depend on Context
+        api = ApiService(this)
+
         // Action bar
         title = getString(R.string.main_action_bar_title)
 
@@ -90,8 +101,10 @@ class MainActivity : AppCompatActivity(), ActionMode.Callback {
     }
 
     private fun onSubscribe(topic: String, baseUrl: String) {
+        // FIXME ignores baseUrl
         Log.d(TAG, "Adding subscription ${topicShortUrl(baseUrl, topic)}")
 
+        // Add subscription to database
         val subscription = Subscription(
             id = Random.nextLong(),
             baseUrl = baseUrl,
@@ -100,6 +113,8 @@ class MainActivity : AppCompatActivity(), ActionMode.Callback {
             lastActive = Date().time/1000
         )
         viewModel.add(subscription)
+
+        // Subscribe to Firebase topic
         FirebaseMessaging
             .getInstance()
             .subscribeToTopic(topic)
@@ -110,9 +125,17 @@ class MainActivity : AppCompatActivity(), ActionMode.Callback {
                 Log.e(TAG, "Subscribing to topic failed: $it")
             }
 
-        // FIXME ignores baseUrl
+        // Fetch cached messages
+        val successFn = { notifications: List<Notification> ->
+            lifecycleScope.launch(Dispatchers.IO) {
+                notifications.forEach { repository.addNotification(it) }
+            }
+            Unit
+        }
+        api.poll(subscription.id, subscription.baseUrl, subscription.topic, successFn, { _ -> })
 
-        onSubscriptionItemClick(subscription) // Add to detail view after adding it
+        // Switch to detail view after adding it
+        onSubscriptionItemClick(subscription)
     }
 
     private fun onSubscriptionItemClick(subscription: Subscription) {
diff --git a/app/src/main/res/menu/detail_action_bar_menu.xml b/app/src/main/res/menu/detail_action_bar_menu.xml
index 852ef14..3f3e160 100644
--- a/app/src/main/res/menu/detail_action_bar_menu.xml
+++ b/app/src/main/res/menu/detail_action_bar_menu.xml
@@ -1,5 +1,6 @@
 <menu xmlns:android="http://schemas.android.com/apk/res/android" >
     <item android:id="@+id/detail_menu_test" android:title="@string/detail_menu_test"/>
     <item android:id="@+id/detail_menu_refresh" android:title="@string/detail_menu_refresh"/>
+    <item android:id="@+id/detail_menu_clear" android:title="@string/detail_menu_clear"/>
     <item android:id="@+id/detail_menu_unsubscribe" android:title="@string/detail_menu_unsubscribe"/>
 </menu>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 7819b7b..86285ef 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -42,6 +42,9 @@
     <string name="detail_how_to_intro">To send notifications to this topic, simply PUT or POST to the topic URL.</string>
     <string name="detail_how_to_example"><![CDATA[ Example (using curl):<br/><tt>$ curl -d \"Hi\" %1$s</tt> ]]></string>
     <string name="detail_how_to_link">For more detailed instructions, check out the ntfy.sh website and documentation.</string>
+    <string name="detail_clear_dialog_message">Do you really want to delete all of the messages you received?</string>
+    <string name="detail_clear_dialog_permanently_delete">Permanently delete</string>
+    <string name="detail_clear_dialog_cancel">Cancel</string>
     <string name="detail_delete_dialog_message">Do you really want to unsubscribe from this topic and delete all of the messages you received?</string>
     <string name="detail_delete_dialog_permanently_delete">Permanently delete</string>
     <string name="detail_delete_dialog_cancel">Cancel</string>
@@ -52,8 +55,9 @@
     <string name="detail_refresh_message_error">Could not refresh topic: %1$s</string>
 
     <!-- Detail activity: Action bar -->
-    <string name="detail_menu_refresh">Force refresh</string>
     <string name="detail_menu_test">Send test notification</string>
+    <string name="detail_menu_refresh">Fetch cached notifications</string>
+    <string name="detail_menu_clear">Clear notifications</string>
     <string name="detail_menu_unsubscribe">Unsubscribe</string>
 
     <!-- Detail activity: Action mode -->