diff --git a/app/src/main/java/com/murrayc/galaxyzoo/app/ClassifyActivity.java b/app/src/main/java/com/murrayc/galaxyzoo/app/ClassifyActivity.java
index afe1d8f7..5759008e 100644
--- a/app/src/main/java/com/murrayc/galaxyzoo/app/ClassifyActivity.java
+++ b/app/src/main/java/com/murrayc/galaxyzoo/app/ClassifyActivity.java
@@ -160,6 +160,10 @@ protected Boolean doInBackground(final Void... params) {
                 return Boolean.FALSE;
             }
 
+            if (isCancelled()) {
+                return Boolean.FALSE;
+            }
+
             return LoginUtils.getLoggedIn(context);
         }
 
@@ -205,6 +209,10 @@ protected Void doInBackground(final Void... params) {
                 return null;
             }
 
+            if (isCancelled()) {
+                return null;
+            }
+
             final AccountManager mgr = AccountManager.get(context);
 
             //Note this needs the GET_ACCOUNTS permission on
@@ -216,12 +224,15 @@ protected Void doInBackground(final Void... params) {
                 return null;
             }
 
+            if (isCancelled()) {
+                return null;
+            }
+
             final Account account = accts[0];
 
             final Bundle extras = new Bundle();
             extras.putBoolean(ContentResolver.SYNC_EXTRAS_MANUAL, true);
 
-
             //Ask the framework to run our SyncAdapter.
             ContentResolver.requestSync(account, Item.AUTHORITY, extras);
 
diff --git a/app/src/main/java/com/murrayc/galaxyzoo/app/LoginActivity.java b/app/src/main/java/com/murrayc/galaxyzoo/app/LoginActivity.java
index 463749f9..90961525 100644
--- a/app/src/main/java/com/murrayc/galaxyzoo/app/LoginActivity.java
+++ b/app/src/main/java/com/murrayc/galaxyzoo/app/LoginActivity.java
@@ -315,6 +315,10 @@ protected Void doInBackground(final Void... params) {
                 return null;
             }
 
+            if (isCancelled()) {
+                return null;
+            }
+
             final String accountName = loginResult.getName();
 
             final AccountManager accountManager = AccountManager.get(context);
diff --git a/app/src/main/java/com/murrayc/galaxyzoo/app/LoginUtils.java b/app/src/main/java/com/murrayc/galaxyzoo/app/LoginUtils.java
index 3d971315..2961fbc6 100644
--- a/app/src/main/java/com/murrayc/galaxyzoo/app/LoginUtils.java
+++ b/app/src/main/java/com/murrayc/galaxyzoo/app/LoginUtils.java
@@ -470,6 +470,10 @@ protected LoginDetails doInBackground(final Void... params) {
                 return null;
             }
 
+            if (isCancelled()) {
+                return null;
+            }
+
             LoginDetails result = null;
 
             try {
@@ -517,6 +521,10 @@ protected Void doInBackground(final Void... params) {
                 return null;
             }
 
+            if (isCancelled()) {
+                return null;
+            }
+
             final LoginUtils.LoginDetails loginDetails = LoginUtils.getAccountLoginDetails(context);
             if(!LoginUtils.getLoggedIn(loginDetails)) {
                 return null;
@@ -527,6 +535,10 @@ protected Void doInBackground(final Void... params) {
                 return null;
             }
 
+            if (isCancelled()) {
+                return null;
+            }
+
             LoginUtils.removeAccount(context, accountName);
 
             LoginUtils.addAnonymousAccount(context);
diff --git a/app/src/main/java/com/murrayc/galaxyzoo/app/QuestionFragment.java b/app/src/main/java/com/murrayc/galaxyzoo/app/QuestionFragment.java
index c71963eb..8725a888 100644
--- a/app/src/main/java/com/murrayc/galaxyzoo/app/QuestionFragment.java
+++ b/app/src/main/java/com/murrayc/galaxyzoo/app/QuestionFragment.java
@@ -681,6 +681,10 @@ protected Void doInBackground(final Void... params) {
                 return null;
             }
 
+            if (isCancelled()) {
+                return null;
+            }
+
             fragment.saveClassificationSync(classificationInProgress);
 
             return null;
diff --git a/app/src/main/java/com/murrayc/galaxyzoo/app/Singleton.java b/app/src/main/java/com/murrayc/galaxyzoo/app/Singleton.java
index fd7b2604..c5a7e26d 100644
--- a/app/src/main/java/com/murrayc/galaxyzoo/app/Singleton.java
+++ b/app/src/main/java/com/murrayc/galaxyzoo/app/Singleton.java
@@ -318,6 +318,10 @@ protected Void doInBackground(final Context... params) {
                 return null;
             }
 
+            if (isCancelled()) {
+                return null;
+            }
+
             final Context context = params[0];
             try {
                 Singleton.ourInstance = new Singleton(context);