diff --git a/android/src/main/java/co/uk/hive/reactnativegeolocation/geofence/GeofenceController.java b/android/src/main/java/co/uk/hive/reactnativegeolocation/geofence/GeofenceController.java
index 5392ade..4c2617a 100644
--- a/android/src/main/java/co/uk/hive/reactnativegeolocation/geofence/GeofenceController.java
+++ b/android/src/main/java/co/uk/hive/reactnativegeolocation/geofence/GeofenceController.java
@@ -2,6 +2,7 @@
 
 import android.os.Build;
 import android.util.Log;
+
 import com.annimon.stream.Optional;
 import com.annimon.stream.Stream;
 import com.annimon.stream.function.Function;
@@ -26,12 +27,23 @@ public class GeofenceController {
     }
 
     public void start(Function<? super Object, ? super Object> successCallback, Function<? super Object, ? super Object> failureCallback) {
-        if (mGeofenceRepository.getGeofences().isEmpty()) {
+        start(successCallback, failureCallback, mGeofenceRepository.getGeofences());
+    }
+
+    public void start(Function<? super Object, ? super Object> successCallback, Function<? super Object, ? super Object> failureCallback, List<Geofence> geofences) {
+        if (geofences.isEmpty()) {
             Log.w(getClass().getSimpleName(), "Starting geofences with none set, exiting");
             return;
         }
-        mGeofenceActivator.setGeofencesActivated(true);
-        mGeofenceEngine.addGeofences(mGeofenceRepository.getGeofences(), successCallback, failureCallback);
+
+        mGeofenceEngine.addGeofences(
+                geofences,
+                successResult -> {
+                    mGeofenceActivator.setGeofencesActivated(true);
+                    return successCallback.apply(successResult);
+                },
+                failureCallback
+        );
     }
 
     public void stop(Function<? super Object, ? super Object> successCallback, Function<? super Object, ? super Object> failureCallback) {
@@ -39,25 +51,44 @@ public void stop(Function<? super Object, ? super Object> successCallback, Funct
             Log.w(getClass().getSimpleName(), "Stopping geofences with none set, exiting");
             return;
         }
-        mGeofenceActivator.setGeofencesActivated(false);
-        List<String> geofenceIds = getGeofenceIds();
+
+        List<String> geofenceIds = getGeofenceIdsToRemove();
         if (!geofenceIds.isEmpty()) {
-            mGeofenceEngine.removeGeofences(geofenceIds, successCallback, failureCallback);
+            mGeofenceEngine.removeGeofences(
+                    geofenceIds,
+                    successResult -> {
+                        mGeofenceActivator.setGeofencesActivated(false);
+                        return successCallback.apply(successResult);
+                    },
+                    failureCallback
+            );
         }
     }
 
     public void restart(Function<? super Object, ? super Object> successCallback, Function<? super Object, ? super Object> failureCallback) {
         if (mGeofenceActivator.areGeofencesActivated()) {
-            start(successCallback, failureCallback);
+            final List<Geofence> geofences = Stream.of(mGeofenceRepository.getGeofences())
+                    .filterNot(GeofenceController::isInvalidGeofence)
+                    .toList();
+
+            start(successCallback, failureCallback, geofences);
         }
     }
 
-    private List<String> getGeofenceIds() {
+    private List<String> getGeofenceIdsToRemove() {
         return Stream.of(mGeofenceRepository.getGeofences())
+                .filterNot(GeofenceController::isInvalidGeofence)
                 .map(Geofence::getId)
                 .toList();
     }
 
+    private static boolean isInvalidGeofence(Geofence geofence) {
+        // Removes geofences where `setGeofencesActivated` was set to `true` before crashing
+        // They cannot be restarted (it'll crash) and they cannot be removed (they were never added)
+        // Geofences added from 1.2.1 should never meet this condition
+        return geofence.getRadius() == 0;
+    }
+
     public void addGeofences(List<Geofence> geofences) {
         mGeofenceRepository.addGeofences(geofences);
     }
diff --git a/android/src/test/java/co/uk/hive/reactnativegeolocation/GeofenceControllerTest.java b/android/src/test/java/co/uk/hive/reactnativegeolocation/GeofenceControllerTest.java
index fe5af8f..e09f39a 100644
--- a/android/src/test/java/co/uk/hive/reactnativegeolocation/GeofenceControllerTest.java
+++ b/android/src/test/java/co/uk/hive/reactnativegeolocation/GeofenceControllerTest.java
@@ -1,19 +1,30 @@
 package co.uk.hive.reactnativegeolocation;
 
-import co.uk.hive.reactnativegeolocation.geofence.*;
+import com.annimon.stream.Stream;
 import com.annimon.stream.function.Function;
+
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
+import org.mockito.invocation.InvocationOnMock;
 import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.stubbing.Answer;
 
 import java.util.Arrays;
 import java.util.List;
 
+import co.uk.hive.reactnativegeolocation.geofence.Geofence;
+import co.uk.hive.reactnativegeolocation.geofence.GeofenceActivator;
+import co.uk.hive.reactnativegeolocation.geofence.GeofenceController;
+import co.uk.hive.reactnativegeolocation.geofence.GeofenceEngine;
+import co.uk.hive.reactnativegeolocation.geofence.GeofenceRepository;
+
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyList;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.BDDMockito.given;
+import static org.mockito.Mockito.doAnswer;
 import static org.mockito.Mockito.verify;
 
 @SuppressWarnings("Convert2Lambda")
@@ -32,11 +43,18 @@ public class GeofenceControllerTest {
     @InjectMocks
     private GeofenceController mSut;
 
-    private List<Geofence> mGeofences = Arrays.asList(
+    private List<Geofence> mMixedGeofences = Arrays.asList(
             TestData.createGeofence("1"),
-            TestData.createGeofence("2"));
+            TestData.createGeofence("2"),
+            TestData.createInvalidGeofence("3")
+    );
+
+    private List<Geofence> mGeofences = mMixedGeofences.subList(0, mMixedGeofences.size() - 1);
+
+    @Mock
+    private Function<? super Object, ? super Object> mSuccessCallback;
 
-    private Function<? super Object, ? super Object> mCallback = new Function<Object, Object>() {
+    private Function<? super Object, ? super Object> mFailureCallback = new Function<Object, Object>() {
         @Override
         public Object apply(Object ignored) {
             return null;
@@ -46,20 +64,34 @@ public Object apply(Object ignored) {
     @Test
     public void startsGeofences() {
         given(mGeofenceRepository.getGeofences()).willReturn(mGeofences);
+        doAnswer(new Answer<Object>() {
+            @Override
+            public Object answer(InvocationOnMock invocation) throws Throwable {
+                return ((Function) invocation.getArgument(1)).apply(null);
+            }
+        }).when(mGeofenceEngine).addGeofences(anyList(), any(Function.class), any(Function.class));
 
-        mSut.start(mCallback, mCallback);
+        mSut.start(mSuccessCallback, mFailureCallback);
 
-        verify(mGeofenceEngine).addGeofences(mGeofences, mCallback, mCallback);
+        verify(mGeofenceEngine).addGeofences(eq(mGeofences), any(Function.class), eq(mFailureCallback));
+        verify(mSuccessCallback).apply(null);
         verify(mGeofenceActivator).setGeofencesActivated(true);
     }
 
     @Test
     public void stopsGeofences() {
         given(mGeofenceRepository.getGeofences()).willReturn(mGeofences);
+        doAnswer(new Answer<Object>() {
+            @Override
+            public Object answer(InvocationOnMock invocation) throws Throwable {
+                return ((Function) invocation.getArgument(1)).apply(null);
+            }
+        }).when(mGeofenceEngine).removeGeofences(anyList(), any(Function.class), any(Function.class));
 
-        mSut.stop(mCallback, mCallback);
+        mSut.stop(mSuccessCallback, mFailureCallback);
 
-        verify(mGeofenceEngine).removeGeofences(Arrays.asList("1", "2"), mCallback, mCallback);
+        verify(mGeofenceEngine).removeGeofences(eq(Arrays.asList("1", "2")), any(Function.class), eq(mFailureCallback));
+        verify(mSuccessCallback).apply(null);
         verify(mGeofenceActivator).setGeofencesActivated(false);
     }
 
@@ -68,12 +100,33 @@ public void restartsGeofences() {
         given(mGeofenceRepository.getGeofences()).willReturn(mGeofences);
         given(mGeofenceActivator.areGeofencesActivated()).willReturn(true);
 
-        mSut.restart(mCallback, mCallback);
+        mSut.restart(mSuccessCallback, mFailureCallback);
+
+        verify(mGeofenceActivator).areGeofencesActivated();
+        verify(mGeofenceEngine).addGeofences(eq(mGeofences), any(), any());
+    }
+
+    @Test
+    public void filtersInvalidGeofencesOnRestart() {
+        given(mGeofenceRepository.getGeofences()).willReturn(mMixedGeofences);
+        given(mGeofenceActivator.areGeofencesActivated()).willReturn(true);
+
+        mSut.restart(mSuccessCallback, mFailureCallback);
 
         verify(mGeofenceActivator).areGeofencesActivated();
         verify(mGeofenceEngine).addGeofences(eq(mGeofences), any(), any());
     }
 
+    @Test
+    public void filtersInvalidGeofencesOnStop() {
+        given(mGeofenceRepository.getGeofences()).willReturn(mMixedGeofences);
+
+        mSut.stop(mSuccessCallback, mFailureCallback);
+
+        final List<String> expectedIds = Stream.of(mGeofences).map(Geofence::getId).toList();
+        verify(mGeofenceEngine).removeGeofences(eq(expectedIds), any(Function.class), eq(mFailureCallback));
+    }
+
     @Test
     public void interactsWithRepository() {
         mSut.addGeofences(mGeofences);
diff --git a/android/src/test/java/co/uk/hive/reactnativegeolocation/TestData.java b/android/src/test/java/co/uk/hive/reactnativegeolocation/TestData.java
index 20c1ef9..68d5b97 100644
--- a/android/src/test/java/co/uk/hive/reactnativegeolocation/TestData.java
+++ b/android/src/test/java/co/uk/hive/reactnativegeolocation/TestData.java
@@ -4,6 +4,10 @@
 
 class TestData {
     static Geofence createGeofence(String id) {
+        return new Geofence(id, 1, 0, 0, false, false, false, 0);
+    }
+
+    static Geofence createInvalidGeofence(String id) {
         return new Geofence(id, 0, 0, 0, false, false, false, 0);
     }
 }
diff --git a/package.json b/package.json
index b5f5dc1..edf7e72 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@connected-home/react-native-geolocation",
-  "version": "1.2.0",
+  "version": "1.2.1",
   "description": "Basic geolocation + geofencing. Delegates to react-native-background-geolocation for iOS.",
   "main": "index.js",
   "scripts": {