diff --git a/platform/darwin/src/MGLMapSnapshotter.mm b/platform/darwin/src/MGLMapSnapshotter.mm
index b6cde57db65..0e13b98b6fc 100644
--- a/platform/darwin/src/MGLMapSnapshotter.mm
+++ b/platform/darwin/src/MGLMapSnapshotter.mm
@@ -108,6 +108,11 @@ - (void)startWithCompletionHandler:(MGLMapSnapshotCompletionHandler)completion
 
 - (void)startWithQueue:(dispatch_queue_t)queue completionHandler:(MGLMapSnapshotCompletionHandler)completion
 {
+    if (!mbgl::Scheduler::GetCurrent()) {
+        [NSException raise:NSInvalidArgumentException
+                    format:@"startWithQueue:completionHandler: should be called from the main thread"];
+    }
+
     if ([self isLoading]) {
         [NSException raise:NSInternalInconsistencyException
                     format:@"Already started this snapshotter."];
diff --git a/platform/ios/Integration Tests/MGLMapViewIntegrationTest.h b/platform/ios/Integration Tests/MGLMapViewIntegrationTest.h
index e4a1e828785..6fb03b7b834 100644
--- a/platform/ios/Integration Tests/MGLMapViewIntegrationTest.h	
+++ b/platform/ios/Integration Tests/MGLMapViewIntegrationTest.h	
@@ -4,6 +4,9 @@
 #define MGLTestFailWithSelf(myself, ...) \
     _XCTPrimitiveFail(myself, __VA_ARGS__)
 
+#define MGLTestAssert(myself, expression, ...) \
+    _XCTPrimitiveAssertTrue(myself, expression, @#expression, __VA_ARGS__)
+
 #define MGLTestAssertNil(myself, expression, ...) \
     _XCTPrimitiveAssertNil(myself, expression, @#expression, __VA_ARGS__)
 
diff --git a/platform/ios/Integration Tests/Snapshotter Tests/MGLMapSnapshotterTest.m b/platform/ios/Integration Tests/Snapshotter Tests/MGLMapSnapshotterTest.m
index d7d013d6e5c..a1a63e40a66 100644
--- a/platform/ios/Integration Tests/Snapshotter Tests/MGLMapSnapshotterTest.m	
+++ b/platform/ios/Integration Tests/Snapshotter Tests/MGLMapSnapshotterTest.m	
@@ -88,14 +88,17 @@ - (void)testAllocatingSnapshotOnBackgroundQueue {
         dispatch_group_t group = dispatch_group_create();
         dispatch_group_enter(group);
 
-        dispatch_async(dispatch_get_main_queue(), ^{
-            [expectation fulfill];
+        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
             dispatch_group_leave(group);
         });
 
         dispatch_group_wait(group, DISPATCH_TIME_FOREVER);
 
         snapshotter = nil;
+
+        dispatch_sync(dispatch_get_main_queue(), ^{
+            [expectation fulfill];
+        });
     });
 
     [self waitForExpectations:@[expectation] timeout:2.0];
@@ -107,11 +110,11 @@ - (void)testMultipleSnapshottersFromBackgroundQueue {
     }
 
     // Crashes with only 1 snapshot
-    NSUInteger numSnapshots = 1;
     CGSize size = self.mapView.bounds.size;
+    CLLocationCoordinate2D coord = CLLocationCoordinate2DMake(30.0, 30.0);
 
     XCTestExpectation *expectation = [self expectationWithDescription:@"snapshots"];
-    expectation.expectedFulfillmentCount = numSnapshots;
+    expectation.expectedFulfillmentCount = 1;
     expectation.assertForOverFulfill = YES;
 
     __weak __typeof__(self) weakself = self;
@@ -119,53 +122,57 @@ - (void)testMultipleSnapshottersFromBackgroundQueue {
     dispatch_queue_attr_t attr = dispatch_queue_attr_make_with_qos_class(DISPATCH_QUEUE_SERIAL, QOS_CLASS_USER_INITIATED, QOS_MIN_RELATIVE_PRIORITY); // also for concurrent
     dispatch_queue_t backgroundQueue = dispatch_queue_create(__PRETTY_FUNCTION__, attr);
 
-    // Crashes with dispatch_apply too
-    // dispatch_apply(numSnapshots, backgroundQueue, ^(size_t run) {
-    // ... let's try a dispatch_async
 
-    for (size_t run = 0; run < numSnapshots; run++) {
+    // Use dispatch_group to keep the backgroundQueue block around (and
+    // so also the MGLMapSnapshotter
+    dispatch_group_t group = dispatch_group_create();
+    dispatch_group_enter(group);
 
-        // Use dispatch_group to keep the backgroundQueue block around (and
-        // so also the MGLMapSnapshotter
-        dispatch_group_t group = dispatch_group_create();
-        dispatch_group_enter(group);
 
-        dispatch_async(backgroundQueue, ^{
+    dispatch_async(backgroundQueue, ^{
 
-            float ratio = (float)run/(float)numSnapshots;
-            float latlon = (ratio*30.0) + ((1-ratio)*40.0);
-            CLLocationCoordinate2D coord = CLLocationCoordinate2DMake(latlon, latlon);
+        MGLMapSnapshotter *snapshotter = snapshotterWithCoordinates(coord, size);
+        XCTAssertNotNil(snapshotter);
 
-            MGLMapSnapshotter *snapshotter = snapshotterWithCoordinates(coord, size);
-            XCTAssertNotNil(snapshotter);
+        MGLMapSnapshotCompletionHandler completion = ^(MGLMapSnapshot * _Nullable snapshot, NSError * _Nullable error) {
 
-            [snapshotter startWithCompletionHandler:^(MGLMapSnapshot * _Nullable snapshot, NSError * _Nullable error) {
+            // This should be the main queue
+            __typeof__(self) strongself = weakself;
 
-                // This should be the main queue
-                __typeof__(self) strongself = weakself;
+            MGLTestAssertNotNil(strongself, strongself);
 
-                MGLTestAssertNotNil(strongself, strongself);
+            MGLTestAssertNotNil(strongself, snapshot);
+            MGLTestAssertNotNil(strongself, snapshot.image);
+            MGLTestAssertNil(strongself, error, @"Snapshot should not error with: %@", error);
 
-                MGLTestAssertNotNil(strongself, snapshot);
-                MGLTestAssertNotNil(strongself, snapshot.image);
-                MGLTestAssertNil(strongself, error, @"Snapshot should not error with: %@", error);
+            // Change this back to XCTAttachmentLifetimeDeleteOnSuccess when we're sure this
+            // test is passing.
+            XCTAttachment *attachment = [XCTAttachment attachmentWithImage:snapshot.image];
+            attachment.lifetime = XCTAttachmentLifetimeKeepAlways;
+            [strongself addAttachment:attachment];
 
-                // Change this back to XCTAttachmentLifetimeDeleteOnSuccess when we're sure this
-                // test is passing.
-                XCTAttachment *attachment = [XCTAttachment attachmentWithImage:snapshot.image];
-                attachment.lifetime = XCTAttachmentLifetimeKeepAlways;
-                [strongself addAttachment:attachment];
-                [expectation fulfill];
+            dispatch_group_leave(group);
+        };
+
+        // untested
+        @try {
+            [snapshotter startWithCompletionHandler:completion];
+            MGLTestFailWithSelf(weakself);
+        }
+        @catch (NSException *exception) {
+            MGLTestAssert(weakself, exception.name == NSInvalidArgumentException);
+            dispatch_group_leave(group);
+        }
 
-                dispatch_group_leave(group);
-            }];
+        // Wait for the snapshot to complete
+        dispatch_group_wait(group, DISPATCH_TIME_FOREVER);
 
-            // Wait for the snapshot to complete
-            dispatch_group_wait(group, DISPATCH_TIME_FOREVER);
+        snapshotter = nil;
 
-            snapshotter = nil;
+        dispatch_sync(dispatch_get_main_queue(), ^{
+            [expectation fulfill];
         });
-    } // end for loop
+    });
 
     [self waitForExpectations:@[expectation] timeout:10.0];
 }