diff --git a/RCTBrowser.m b/RCTBrowser.m
index 0c86e6e..a47ed1e 100644
--- a/RCTBrowser.m
+++ b/RCTBrowser.m
@@ -6,7 +6,9 @@ @implementation RCTBrowser
 
 RCT_EXPORT_MODULE()
 
-RCT_EXPORT_METHOD(presentUrl:(NSString *)url withOptions:(NSDictionary *)options) {
+RCT_EXPORT_METHOD(presentUrl:(NSString *)url
+                  withOptions:(NSDictionary *)options
+                  modalCompletion:(RCTResponseSenderBlock)modalCompletionHandler) {
 
     TOWebViewController *webVC = [[TOWebViewController alloc] initWithURLString:url];
 
@@ -31,8 +33,6 @@ @implementation RCTBrowser
             webVC.disableContextualPopupMenu = ([obj isEqual: @(YES)]);
         } else if ([key isEqualToString:@"hideWebViewBoundaries"]) {
             webVC.hideWebViewBoundaries = ([obj isEqual: @(YES)]);
-        } else if ([key isEqualToString:@"modalCompletionHandler"]) {
-            // TODO: turn this into a callback
         } else if ([key isEqualToString:@"shouldStartLoadRequestHandler"]) {
             // TODO: turn this into a callback
         } else if ([key isEqualToString:@"buttonTintColor"]) {
@@ -42,6 +42,10 @@ @implementation RCTBrowser
         }
     }];
 
+    webVC.modalCompletionHandler = ^(void) {
+        modalCompletionHandler(@[[NSNull null]]);
+    };
+
     UIViewController *rootVC = [[UIApplication sharedApplication] keyWindow].rootViewController;
     UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:webVC];
 
diff --git a/index.ios.js b/index.ios.js
index 3f39a41..dbacd1b 100644
--- a/index.ios.js
+++ b/index.ios.js
@@ -10,7 +10,11 @@ var Browser = NativeModules.Browser;
 
 var RCTBrowserExport = {
   open: function(url, options={}) {
-    Browser.presentUrl(url, options);
+    Browser.presentUrl(url, options, function(err) {
+      if (options.modalCompletionHandler) {
+        options.modalCompletionHandler();
+      }
+    });
   },
 };