diff --git a/app/src/main/java/org/obd/graphs/preferences/ConnectionTypeListPreference.kt b/app/src/main/java/org/obd/graphs/preferences/ConnectionTypeListPreference.kt
new file mode 100644
index 00000000..9e0393fe
--- /dev/null
+++ b/app/src/main/java/org/obd/graphs/preferences/ConnectionTypeListPreference.kt
@@ -0,0 +1,46 @@
+ /**
+ * Copyright 2019-2026, Tomasz Żebrowski
+ *
+ * <p>Licensed to the Apache Software Foundation (ASF) under one or more contributor license
+ * agreements. See the NOTICE file distributed with this work for additional information regarding
+ * copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License. You may obtain a
+ * copy of the License at
+ *
+ * <p>http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * <p>Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.obd.graphs.preferences
+
+import android.content.Context
+import android.util.AttributeSet
+import android.util.Log
+import androidx.preference.ListPreference
+import org.obd.graphs.BuildConfig
+
+private const val TAG = "ConnectionType"
+private const val MOCK_CONNECTION_TYPE = "mock"
+
+class ConnectionTypeListPreference(
+    context: Context,
+    attrs: AttributeSet?,
+) : ListPreference(context, attrs) {
+    init {
+        if (BuildConfig.DEBUG) {
+            if (Log.isLoggable(TAG, Log.DEBUG)) {
+                Log.d(TAG, "Keeping mock connection type")
+            }
+        } else {
+            if (Log.isLoggable(TAG, Log.DEBUG)) {
+                Log.d(TAG, "Filtering out mock connection type")
+            }
+
+            entries = entries.filter { p -> p != MOCK_CONNECTION_TYPE }.toTypedArray()
+            entryValues = entryValues.filter { p -> p != MOCK_CONNECTION_TYPE }.toTypedArray()
+        }
+    }
+}
diff --git a/app/src/main/res/xml/preferences.xml b/app/src/main/res/xml/preferences.xml
index 6751c758..6691dbf2 100644
--- a/app/src/main/res/xml/preferences.xml
+++ b/app/src/main/res/xml/preferences.xml
@@ -131,7 +131,7 @@
                         android:title="@string/pref.connection.connection_timeout"
                         app:useSimpleSummaryProvider="true" />
 
-                    <ListPreference
+                    <org.obd.graphs.preferences.ConnectionTypeListPreference
                         android:defaultValue="bluetooth"
                         android:dialogTitle="@string/pref.connection.connection_type_dialog"
                         android:entries="@array/pref.connection_type_array"
@@ -166,7 +166,6 @@
                             android:title="@string/pref.usb.baud_rate"
                             app:singleLineTitle="false"
                             app:useSimpleSummaryProvider="true" />
-
                     </PreferenceCategory>
 
                     <PreferenceCategory