diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8a3ad5f42..48871fdee 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,21 @@
+<a name="5.1.1"></a>
+## [5.1.1](https://github.com/NativeScript/NativeScript/compare/5.1.0...5.1.1) (2018-12-19)
+
+
+### Bug Fixes
+
+* **android:** animator restore logic on simulated nav ([#6710](https://github.com/NativeScript/NativeScript/issues/6710)) ([54b6df6](https://github.com/NativeScript/NativeScript/commit/54b6df6))
+* **android:** failure saving state in mixed parent/nested frame nav ([#6719](https://github.com/NativeScript/NativeScript/issues/6719)) ([e5f110f](https://github.com/NativeScript/NativeScript/commit/e5f110f))
+* **android:** nested fragment disappears on parent fragment removal ([#6677](https://github.com/NativeScript/NativeScript/issues/6677)) ([c084660](https://github.com/NativeScript/NativeScript/commit/c084660))
+
+
+### Features
+
+* **tns-platform-declarations:** Generate iOS typings from iOS 12.1 SDK ([#6693](https://github.com/NativeScript/NativeScript/issues/6693)) ([1c0218e](https://github.com/NativeScript/NativeScript/commit/1c0218e))
+* **view:** added iOS parameter for modal presentation style ([#6409](https://github.com/NativeScript/NativeScript/issues/6409)) ([540b2b4](https://github.com/NativeScript/NativeScript/commit/540b2b4))
+
+
+
 <a name="5.1.0"></a>
 # [5.1.0](https://github.com/NativeScript/NativeScript/compare/5.0.5...5.1.0) (2018-12-05)
 
diff --git a/apps/app/css-perf-test/main-page.ts b/apps/app/css-perf-test/main-page.ts
index c22a93868..eccc8d67c 100644
--- a/apps/app/css-perf-test/main-page.ts
+++ b/apps/app/css-perf-test/main-page.ts
@@ -1,4 +1,4 @@
-import {EventData as ObservableEventData } from "tns-core-modules/data/observable";
+import { EventData as ObservableEventData } from "tns-core-modules/data/observable";
 
 export function navigatedTo(args: ObservableEventData) {
     setTimeout(() => {
diff --git a/apps/app/cuteness.io/main-page.ts b/apps/app/cuteness.io/main-page.ts
index 6fc3b9429..b2a89b2c3 100644
--- a/apps/app/cuteness.io/main-page.ts
+++ b/apps/app/cuteness.io/main-page.ts
@@ -1,7 +1,7 @@
-import {EventData as ObservableEventData } from "tns-core-modules/data/observable";
+import { EventData as ObservableEventData } from "tns-core-modules/data/observable";
 import { Page } from "tns-core-modules/ui/page";
-import {ItemEventData as ListViewItemEventData } from "tns-core-modules/ui/list-view";
-import {topmost as topmostFrame } from "tns-core-modules/ui/frame";
+import { ItemEventData as ListViewItemEventData } from "tns-core-modules/ui/list-view";
+import { topmost as topmostFrame } from "tns-core-modules/ui/frame";
 import { AppViewModel } from "./reddit-app-view-model";
 
 var appViewModel = new AppViewModel();
diff --git a/tns-core-modules/package.json b/tns-core-modules/package.json
index 17a3e7421..444817415 100644
--- a/tns-core-modules/package.json
+++ b/tns-core-modules/package.json
@@ -1,7 +1,7 @@
 {
   "name": "tns-core-modules",
   "description": "Telerik NativeScript Core Modules",
-  "version": "5.2.0",
+  "version": "5.1.1",
   "homepage": "https://www.nativescript.org",
   "repository": {
     "type": "git",
@@ -26,7 +26,7 @@
   "license": "Apache-2.0",
   "typings": "tns-core-modules.d.ts",
   "dependencies": {
-    "tns-core-modules-widgets": "next",
+    "tns-core-modules-widgets": "5.1.2",
     "tslib": "^1.9.3"
   },
   "devDependencies": {
@@ -38,8 +38,8 @@
   },
   "nativescript": {
     "platforms": {
-      "ios": "4.0.0",
-      "android": "4.0.0"
+      "ios": "5.0.0",
+      "android": "5.0.0"
     }
   },
   "snapshot": {
@@ -52,4 +52,4 @@
       }
     }
   }
-}
+}
\ No newline at end of file
diff --git a/tns-core-modules/ui/frame/frame.android.ts b/tns-core-modules/ui/frame/frame.android.ts
index 1f56a8eb2..71e39e4b7 100644
--- a/tns-core-modules/ui/frame/frame.android.ts
+++ b/tns-core-modules/ui/frame/frame.android.ts
@@ -527,10 +527,22 @@ function getAnimatorState(entry: BackstackEntry): AnimatorState {
 
 function restoreAnimatorState(entry: BackstackEntry, snapshot: AnimatorState): void {
     const expandedEntry = <any>entry;
-    expandedEntry.enterAnimator = snapshot.enterAnimator;
-    expandedEntry.exitAnimator = snapshot.exitAnimator;
-    expandedEntry.popEnterAnimator = snapshot.popEnterAnimator;
-    expandedEntry.popExitAnimator = snapshot.popExitAnimator;
+    if (snapshot.enterAnimator) {
+        expandedEntry.enterAnimator = snapshot.enterAnimator;
+    }
+    
+    if (snapshot.exitAnimator) {
+        expandedEntry.exitAnimator = snapshot.exitAnimator;
+    }
+
+    if (snapshot.popEnterAnimator) {
+        expandedEntry.popEnterAnimator = snapshot.popEnterAnimator;
+    }
+    
+    if (snapshot.popExitAnimator) {
+        expandedEntry.popExitAnimator = snapshot.popExitAnimator;
+    }
+
     expandedEntry.transitionName = snapshot.transitionName;
 }
 
@@ -891,6 +903,12 @@ class FragmentCallbacksImplementation implements AndroidFragmentCallbacks {
             return null;
         }
 
+        // [nested frames / fragments] see https://github.com/NativeScript/NativeScript/issues/6629
+        // retaining reference to a destroyed fragment here somehow causes a cryptic 
+        // "IllegalStateException: Failure saving state: active fragment has cleared index: -1" 
+        // in a specific mixed parent / nested frame navigation scenario
+        entry.fragment = null;
+
         const page = entry.resolvedPage;
         if (!page) {
             traceError(`${fragment}.onDestroy: entry has no resolvedPage`);
diff --git a/tns-platform-declarations/package.json b/tns-platform-declarations/package.json
index b3d093a34..826c973d7 100644
--- a/tns-platform-declarations/package.json
+++ b/tns-platform-declarations/package.json
@@ -1,6 +1,6 @@
 {
   "name": "tns-platform-declarations",
-  "version": "5.2.0",
+  "version": "5.1.1",
   "description": "Platform-specific TypeScript declarations for NativeScript for accessing native objects",
   "main": "",
   "scripts": {