diff --git a/app/components/TaskItem.tsx b/app/components/TaskItem.tsx
index 3eca151..f652e6f 100644
--- a/app/components/TaskItem.tsx
+++ b/app/components/TaskItem.tsx
@@ -1,6 +1,6 @@
 import React from 'react';
 import Realm from 'realm';
-import {View, Text, Pressable, StyleSheet} from 'react-native';
+import {View, Text, Pressable, StyleSheet, TouchableOpacity} from 'react-native';
 
 import {shadows} from '../styles/shadows';
 import colors from '../styles/colors';
@@ -33,9 +33,9 @@ export const TaskItem = React.memo<TaskItemProps>(
           </Pressable>
         </View>
         <View>
-          <Pressable onPress={onAddSubItems}>
-            <Text style={styles.edit}>Edit first item</Text>
-          </Pressable>
+          <TouchableOpacity onPress={onAddSubItems}>
+            <Text style={styles.edit}>{`Toggle address (object <-> null)`}</Text>
+          </TouchableOpacity>
           <Text style={styles.subItems}>SubItems: {JSON.stringify(task.items)}</Text>
         </View>
       </>
diff --git a/app/components/TaskManager.tsx b/app/components/TaskManager.tsx
index 50e4b19..b48944f 100644
--- a/app/components/TaskManager.tsx
+++ b/app/components/TaskManager.tsx
@@ -69,8 +69,13 @@ export const TaskManager: React.FC<{
 
   const handleAddSubItems = useCallback((task: Task & Realm.Object): void => {
       realm.write(() => {
-          // different behaviour on Realm 12, it pushes new item instead of updating one
-          task.items[0] = {name: 'First item changed'}
+          // different behaviour on Realm 12, it doesn't allow setting null for embedded schema field,
+          // but it can be null on init app
+          const firstItem = task.items[0]
+          firstItem['address'] = !firstItem.address ? {
+              city: 'Warsaw',
+              country: 'PL'
+          } : null
       });
   }, [realm])
 
diff --git a/app/models/Task.ts b/app/models/Task.ts
index 145c31b..476d061 100644
--- a/app/models/Task.ts
+++ b/app/models/Task.ts
@@ -51,7 +51,19 @@ export class ItemSchema extends Realm.Object {
     name: 'ItemSchema',
     embedded: true,
     properties: {
-      name: 'string'
+      name: 'string',
+      address: 'AddressSchema'
+    },
+  };
+}
+
+export class AddressSchema extends Realm.Object {
+  static schema: Realm.ObjectSchema = {
+    name: 'AddressSchema',
+    embedded: true,
+    properties: {
+      city: 'string',
+      country: 'string'
     },
   };
 }
\ No newline at end of file
diff --git a/app/models/index.ts b/app/models/index.ts
index 060f7bf..168de11 100644
--- a/app/models/index.ts
+++ b/app/models/index.ts
@@ -1,3 +1,3 @@
-import {ItemSchema, Task} from './Task';
+import {AddressSchema, ItemSchema, Task} from './Task';
 
-export const schemas = [Task, ItemSchema];
+export const schemas = [Task, ItemSchema, AddressSchema];