diff --git a/xwords4/android/app/src/main/java/org/eehouse/android/xw4/DictListPreference.java b/xwords4/android/app/src/main/java/org/eehouse/android/xw4/DictListPreference.java
index 1f2a2b6d6..a300f4f43 100644
--- a/xwords4/android/app/src/main/java/org/eehouse/android/xw4/DictListPreference.java
+++ b/xwords4/android/app/src/main/java/org/eehouse/android/xw4/DictListPreference.java
@@ -54,6 +54,9 @@ public class DictListPreference extends XWListPreference {
             curLang = LocUtils.getString( context, R.string.lang_name_english );
         }
         ISOCode isoCode = DictLangCache.getLangIsoCode( context, curLang );
+        if ( null == isoCode ) { // work around crash reported via Play Store
+            isoCode = Utils.ISO_EN;
+        }
 
         DictUtils.DictAndLoc[] dals = DictUtils.dictList( context  );
         ArrayList<String> dictEntries = new ArrayList<>();
diff --git a/xwords4/android/app/src/main/java/org/eehouse/android/xw4/MQTTUtils.java b/xwords4/android/app/src/main/java/org/eehouse/android/xw4/MQTTUtils.java
index 46f18da7d..58db4364a 100644
--- a/xwords4/android/app/src/main/java/org/eehouse/android/xw4/MQTTUtils.java
+++ b/xwords4/android/app/src/main/java/org/eehouse/android/xw4/MQTTUtils.java
@@ -1,7 +1,7 @@
 /* -*- compile-command: "find-and-gradle.sh inXw4dDeb"; -*- */
 /*
- * Copyright 2009 - 2020 by Eric House (xwords@eehouse.org).  All
- * rights reserved.
+ * Copyright 2009 - 2022 by Eric House (xwords@eehouse.org).  All rights
+ * reserved.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
@@ -23,6 +23,7 @@ package org.eehouse.android.xw4;
 import android.content.Context;
 import android.content.Intent;
 import android.os.Build;
+import android.text.TextUtils;
 
 import org.eclipse.paho.client.mqttv3.IMqttActionListener;
 import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken;
@@ -472,7 +473,7 @@ public class MQTTUtils extends Thread
                             switch ( ii ) {
                             case 0:
                                 action = "unsubscribe";
-                                token = client.unsubscribe( mDevID );
+                                token = client.unsubscribe( mTopics );
                                 break;      // not continue, which skips the Log() below
                             case 1:
                                 action = "disconnect";
@@ -617,7 +618,7 @@ public class MQTTUtils extends Thread
         setState( State.SUBSCRIBING );
         try {
             mClient.subscribe( mTopics, qoss, null, this );
-            // Log.d( TAG, "subscribed to %s", mTopic );
+            // Log.d( TAG, "subscribed to %s", TextUtils.join( ", ", mTopics ) );
         } catch ( MqttException ex ) {
             ex.printStackTrace();
         } catch ( Exception ex ) {
diff --git a/xwords4/android/app/src/main/java/org/eehouse/android/xw4/jni/CommonPrefs.java b/xwords4/android/app/src/main/java/org/eehouse/android/xw4/jni/CommonPrefs.java
index bae44c6d8..bacba9703 100644
--- a/xwords4/android/app/src/main/java/org/eehouse/android/xw4/jni/CommonPrefs.java
+++ b/xwords4/android/app/src/main/java/org/eehouse/android/xw4/jni/CommonPrefs.java
@@ -26,7 +26,7 @@ import android.content.res.Configuration;
 import android.content.res.Resources;
 import android.net.Uri;
 import android.os.Build;
-import android.preference.PreferenceManager;
+import androidx.preference.PreferenceManager;
 
 import org.eehouse.android.xw4.Assert;
 import org.eehouse.android.xw4.DictUtils;