diff --git a/xwords4/android/app/src/main/java/org/eehouse/android/xw4/GameConfigDelegate.java b/xwords4/android/app/src/main/java/org/eehouse/android/xw4/GameConfigDelegate.java
index 768daab06..eb29dbe7d 100644
--- a/xwords4/android/app/src/main/java/org/eehouse/android/xw4/GameConfigDelegate.java
+++ b/xwords4/android/app/src/main/java/org/eehouse/android/xw4/GameConfigDelegate.java
@@ -80,6 +80,7 @@ public class GameConfigDelegate extends DelegateBase
     private CheckBox m_gameLockedCheck;
     private boolean m_isLocked;
     private boolean m_haveClosed;
+    private boolean mSub7HintShown;
 
     private CommsConnTypeSet m_conTypes;
     private Button m_addPlayerButton;
@@ -687,6 +688,20 @@ public class GameConfigDelegate extends DelegateBase
             setChecked( R.id.trade_sub_seven, m_gi.tradeSub7 );
             setChecked( R.id.pick_faceup, m_gi.allowPickTiles );
 
+            findViewById( R.id.trade_sub_seven )
+                .setOnClickListener( new View.OnClickListener() {
+                        @Override
+                        public void onClick( View view ) {
+                            if ( !mSub7HintShown ) {
+                                mSub7HintShown = true;
+                                makeNotAgainBuilder( R.string.key_na_sub7new,
+                                                     R.string.sub_seven_allowed_sum )
+                                    .setTitle( R.string.new_feature_title )
+                                    .show();
+                            }
+                        }
+                    } );
+
             setBoardsizeSpinner();
 
             final int[] curSel = {-1};
@@ -838,6 +853,7 @@ public class GameConfigDelegate extends DelegateBase
         return handled;
     }
 
+    @Override
     public void onClick( View view )
     {
         if ( isFinishing() ) {
diff --git a/xwords4/android/app/src/main/res/values/common_rsrc.xml b/xwords4/android/app/src/main/res/values/common_rsrc.xml
index ca89f2d15..65cd9d368 100644
--- a/xwords4/android/app/src/main/res/values/common_rsrc.xml
+++ b/xwords4/android/app/src/main/res/values/common_rsrc.xml
@@ -167,6 +167,7 @@
   <string name="key_na_newFeatureFilter">key_na_newFeatureFilter</string>
   <string name="key_na_customXWD">key_na_customXWD</string>
   <string name="key_na_traysize">key_na_traysize</string>
+  <string name="key_na_sub7new">key_na_sub7new</string>
 
   <string name="key_na_dupstatus_host">key_na_dupstatus_host</string>
   <string name="key_na_dupstatus_guest">key_na_dupstatus_guest</string>