diff --git a/res/color/button_bar_text.xml b/res/color/button_bar_text.xml
new file mode 100644
index 0000000..c670d2d
--- /dev/null
+++ b/res/color/button_bar_text.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+     Copyright (C) 2015 The CyanogenMod Project
+
+     Licensed 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
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     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.
+-->
+
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:state_enabled="false" android:color="@color/button_bar_text_disabled" />
+    <item android:color="@color/button_bar_text_enabled" />
+</selector>
diff --git a/res/layout/choose_data_sim_page.xml b/res/layout/choose_data_sim_page.xml
index d470dbd..c93a89f 100644
--- a/res/layout/choose_data_sim_page.xml
+++ b/res/layout/choose_data_sim_page.xml
@@ -21,13 +21,6 @@
 
     <include layout="@layout/header" />
 
-    <ProgressBar
-        android:id="@+id/progress"
-        style="?android:attr/progressBarStyleHorizontal"
-        android:indeterminateOnly="true"
-        android:layout_width="match_parent"
-        android:layout_height="8dp" />
-
     <FrameLayout android:id="@+id/page"
                  android:layout_width="match_parent"
                  android:layout_height="0dp"
@@ -59,6 +52,15 @@
 
             </LinearLayout>
         </ScrollView>
+
+        <ProgressBar
+            android:id="@+id/progress"
+            style="?android:attr/progressBarStyleHorizontal"
+            android:indeterminateOnly="true"
+            android:layout_width="match_parent"
+            android:layout_height="8dp"
+            android:layout_gravity="top"
+            android:visibility="gone"/>
     </FrameLayout>
 </LinearLayout>
 
diff --git a/res/values/colors.xml b/res/values/colors.xml
index 7943291..34110b7 100644
--- a/res/values/colors.xml
+++ b/res/values/colors.xml
@@ -24,7 +24,8 @@
     <color name="accent">#009789</color>
     <color name="primary_text">#8a000000</color>
     <color name="secondary_text">#727272</color>
-    <color name="button_bar_text">#1e1e1e</color>
+    <color name="button_bar_text_enabled">#ff1e1e1e</color>
+    <color name="button_bar_text_disabled">#321e1e1e</color>
     <color name="divider">#40000000</color>
     <color name="header_bg">@color/primary</color>
     <color name="header_condensed_bg">@color/primary_dark</color>
diff --git a/src/com/cyanogenmod/setupwizard/setup/ChooseDataSimPage.java b/src/com/cyanogenmod/setupwizard/setup/ChooseDataSimPage.java
index af123e0..e053399 100644
--- a/src/com/cyanogenmod/setupwizard/setup/ChooseDataSimPage.java
+++ b/src/com/cyanogenmod/setupwizard/setup/ChooseDataSimPage.java
@@ -33,6 +33,7 @@ import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.animation.AnimationUtils;
+import android.widget.Button;
 import android.widget.CheckBox;
 import android.widget.ImageView;
 import android.widget.ProgressBar;
@@ -50,6 +51,8 @@ public class ChooseDataSimPage extends SetupPage {
 
     public static final String TAG = "ChooseDataSimPage";
 
+    private static final String CHANGE_DATA_SIM_ID_EXTRA = ".changingToId";
+
     public ChooseDataSimPage(Context context, SetupDataCallbacks callbacks) {
         super(context, callbacks);
     }
@@ -85,6 +88,8 @@ public class ChooseDataSimPage extends SetupPage {
         private SparseArray<TextView> mNameViews;
         private SparseArray<ImageView> mSignalViews;
         private SparseArray<CheckBox> mCheckBoxes;
+        private SparseArray<View> mRows;
+        private Button mNextButton;
 
         private TelephonyManager mPhone;
         private SparseArray<SubscriptionInfo> mSubInfoRecords;
@@ -93,16 +98,24 @@ public class ChooseDataSimPage extends SetupPage {
         private SparseArray<PhoneStateListener> mPhoneStateListeners;
 
         private boolean mIsAttached = false;
+        private boolean mRadioReady = false;
 
         private Context mContext;
         private SubscriptionManager mSubscriptionManager;
 
+        private int mCurrentDataPhoneId;
+        private int mChangingToDataPhoneId;
+
         private final Handler mHandler = new Handler();
 
         private final Runnable mRadioReadyRunnable = new Runnable() {
             @Override
             public void run() {
-                hideWaitForRadio();
+                // If we timeout out waiting for the radio, Oh well.
+                if (!mRadioReady) {
+                    mRadioReady = true;
+                    checkForRadioReady();
+                }
             }
         };
 
@@ -110,9 +123,9 @@ public class ChooseDataSimPage extends SetupPage {
             @Override
             public void onClick(View view) {
                 SubscriptionInfo subInfoRecord = (SubscriptionInfo)view.getTag();
-                if (subInfoRecord != null) {
-                    mSubscriptionManager.setDefaultDataSubId(subInfoRecord.getSubscriptionId());
-                    setDataSubChecked(subInfoRecord);
+                if (subInfoRecord != null &&
+                        subInfoRecord.getSimSlotIndex() != mCurrentDataPhoneId) {
+                    changeDataSub(subInfoRecord);
                 }
             }
         };
@@ -121,6 +134,7 @@ public class ChooseDataSimPage extends SetupPage {
         protected void initializePage() {
             mPageView = (ViewGroup)mRootView.findViewById(R.id.page_view);
             mProgressBar = (ProgressBar) mRootView.findViewById(R.id.progress);
+            mNextButton = (Button) getActivity().findViewById(R.id.next_button);
             List<SubscriptionInfo> subInfoRecords = mSubscriptionManager.getActiveSubscriptionInfoList();
             int simCount =
                     subInfoRecords != null ? subInfoRecords.size() : 0;
@@ -131,6 +145,7 @@ public class ChooseDataSimPage extends SetupPage {
             mNameViews = new SparseArray<TextView>(simCount);
             mSignalViews = new SparseArray<ImageView>(simCount);
             mCheckBoxes = new SparseArray<CheckBox>(simCount);
+            mRows = new SparseArray<View>(simCount);
             mServiceStates = new SparseArray<ServiceState>(simCount);
             mSignalStrengths = new SparseArray<SignalStrength>(simCount);
             mPhoneStateListeners = new SparseArray<PhoneStateListener>(simCount);
@@ -145,6 +160,7 @@ public class ChooseDataSimPage extends SetupPage {
                 mNameViews.put(slot, (TextView) simRow.findViewById(R.id.sim_title));
                 mSignalViews.put(slot, (ImageView) simRow.findViewById(R.id.signal));
                 mCheckBoxes.put(slot, (CheckBox) simRow.findViewById(R.id.enable_check));
+                mRows.put(slot, simRow);
                 mPhoneStateListeners.put(slot, createPhoneStateListener(subInfoRecord));
                 mPageView.addView(inflater.inflate(R.layout.divider, null));
             }
@@ -162,6 +178,10 @@ public class ChooseDataSimPage extends SetupPage {
             super.onCreate(savedInstanceState);
             mContext = getActivity().getApplicationContext();
             mSubscriptionManager = SubscriptionManager.from(mContext);
+            mCurrentDataPhoneId = mSubscriptionManager.getDefaultDataPhoneId();
+            mChangingToDataPhoneId = (savedInstanceState == null) ?
+                    mCurrentDataPhoneId :
+                    savedInstanceState.getInt(CHANGE_DATA_SIM_ID_EXTRA, mCurrentDataPhoneId);
         }
 
         @Override
@@ -172,18 +192,24 @@ public class ChooseDataSimPage extends SetupPage {
             for (int i = 0; i < mPhoneStateListeners.size(); i++) {
                 mPhone.listen(mPhoneStateListeners.valueAt(i),
                         PhoneStateListener.LISTEN_SERVICE_STATE
-                                | PhoneStateListener.LISTEN_SIGNAL_STRENGTHS);
+                                | PhoneStateListener.LISTEN_SIGNAL_STRENGTHS
+                                | PhoneStateListener.LISTEN_DATA_CONNECTION_STATE
+                );
             }
+            mRadioReady = SetupWizardUtils.isRadioReady(mContext, null);
             updateSignalStrengths();
             updateCurrentDataSub();
-            if (SetupWizardUtils.isRadioReady(mContext, null)) {
-                hideWaitForRadio();
-            } else if (mTitleView != null) {
-                mTitleView.setText(R.string.loading);
-                mHandler.postDelayed(mRadioReadyRunnable, SetupWizardApp.RADIO_READY_TIMEOUT);
+            checkForRadioReady();
+            if (mRadioReady) {
+                checkSimChangingState();
             }
         }
 
+        @Override
+        public void onSaveInstanceState(Bundle outState) {
+            outState.putInt(CHANGE_DATA_SIM_ID_EXTRA, mChangingToDataPhoneId);
+        }
+
         @Override
         public void onPause() {
             super.onPause();
@@ -204,25 +230,66 @@ public class ChooseDataSimPage extends SetupPage {
 
                 @Override
                 public void onServiceStateChanged(ServiceState state) {
-                    if (SetupWizardUtils.isRadioReady(mContext, state)) {
-                        hideWaitForRadio();
-                    }
+                    mRadioReady = SetupWizardUtils.isRadioReady(mContext, state);
+                    checkForRadioReady();
                     mServiceStates.put(subInfoRecord.getSimSlotIndex(), state);
                     updateSignalStrength(subInfoRecord);
                 }
+
+                @Override
+                public void onDataConnectionStateChanged(int state) {
+                    mCurrentDataPhoneId = mSubscriptionManager.getDefaultDataPhoneId();
+                    checkSimChangingState();
+                }
             };
         }
 
-        private void hideWaitForRadio() {
-            if (getUserVisibleHint() && mProgressBar.isShown()) {
+        private void checkForRadioReady() {
+            if (mRadioReady) {
                 mHandler.removeCallbacks(mRadioReadyRunnable);
+                hideProgress();
+                mNextButton.setEnabled(true);
+                showPage();
+                return;
+            } else {
                 if (mTitleView != null) {
-                    mTitleView.setText(mPage.getTitleResId());
+                    mTitleView.setText(R.string.loading);
                 }
-                mProgressBar.setVisibility(View.GONE);
-                mPageView.setVisibility(View.VISIBLE);
+                mNextButton.setEnabled(false);
+                showProgress();
+                if (!mHandler.hasCallbacks(mRadioReadyRunnable)) {
+                    mHandler.postDelayed(mRadioReadyRunnable, SetupWizardApp.RADIO_READY_TIMEOUT);
+                }
+            }
+        }
+
+        private void showPage() {
+            final Context context = getActivity();
+            if (mTitleView != null) {
+                mTitleView.setText(mPage.getTitleResId());
+            }
+            mPageView.setVisibility(View.VISIBLE);
+            if (context != null && getUserVisibleHint() && !mPageView.isShown()) {
                 mPageView.startAnimation(
-                        AnimationUtils.loadAnimation(getActivity(), R.anim.translucent_enter));
+                        AnimationUtils.loadAnimation(context, R.anim.translucent_enter));
+            }
+        }
+
+        private void showProgress() {
+            final Context context = getActivity();
+            if (context != null && getUserVisibleHint() && !mProgressBar.isShown()) {
+                mProgressBar.setVisibility(View.VISIBLE);
+                mProgressBar.startAnimation(
+                        AnimationUtils.loadAnimation(context, R.anim.translucent_enter));
+            }
+        }
+
+        private void hideProgress() {
+            final Context context = getActivity();
+            if (context != null && getUserVisibleHint() && mProgressBar.isShown()) {
+                mProgressBar.startAnimation(
+                        AnimationUtils.loadAnimation(context, R.anim.translucent_exit));
+                mProgressBar.setVisibility(View.INVISIBLE);
             }
         }
 
@@ -234,6 +301,29 @@ public class ChooseDataSimPage extends SetupPage {
             }
         }
 
+        private void changeDataSub(SubscriptionInfo subInfoRecord) {
+            if (mChangingToDataPhoneId != subInfoRecord.getSimSlotIndex()) {
+                mChangingToDataPhoneId = subInfoRecord.getSimSlotIndex();
+                mSubscriptionManager.setDefaultDataSubId(subInfoRecord.getSubscriptionId());
+                setDataSubChecked(subInfoRecord);
+            }
+            checkSimChangingState();
+        }
+
+        private void checkSimChangingState() {
+            if (mIsAttached && mRadioReady) {
+                if (mCurrentDataPhoneId != mChangingToDataPhoneId) {
+                    showProgress();
+                    mNextButton.setEnabled(false);
+                    enableRows(false);
+                } else {
+                    hideProgress();
+                    mNextButton.setEnabled(true);
+                    enableRows(true);
+                }
+            }
+        }
+
         private void setDataSubChecked(SubscriptionInfo subInfoRecord) {
             if (mIsAttached) {
                 for (int i = 0; i < mCheckBoxes.size(); i++) {
@@ -260,6 +350,12 @@ public class ChooseDataSimPage extends SetupPage {
             }
         }
 
+        private void enableRows(boolean enabled) {
+            for (int i = 0; i < mRows.size(); i++) {
+                mRows.get(i).setEnabled(enabled);
+            }
+        }
+
         private void updateCarrierText(SubscriptionInfo subInfoRecord) {
             if (mIsAttached) {
                 String name = mPhone.getNetworkOperatorName(subInfoRecord.getSubscriptionId());
diff --git a/src/com/cyanogenmod/setupwizard/ui/SetupWizardActivity.java b/src/com/cyanogenmod/setupwizard/ui/SetupWizardActivity.java
index afa861a..373e7e8 100644
--- a/src/com/cyanogenmod/setupwizard/ui/SetupWizardActivity.java
+++ b/src/com/cyanogenmod/setupwizard/ui/SetupWizardActivity.java
@@ -265,8 +265,8 @@ public class SetupWizardActivity extends Activity implements SetupDataCallbacks,
             mButtonBar.setBackgroundResource(R.color.button_bar_background);
             mNextButton.setCompoundDrawablesWithIntrinsicBounds(null, null,
                     getDrawable(R.drawable.ic_chevron_right_dark), null);
-            mNextButton.setTextColor(resources.getColor(R.color.button_bar_text));
-            mPrevButton.setTextColor(resources.getColor(R.color.button_bar_text));
+            mNextButton.setTextColor(resources.getColorStateList(R.color.button_bar_text));
+            mPrevButton.setTextColor(resources.getColorStateList(R.color.button_bar_text));
         }
     }