Add info about custom setters

source/includes/api-details/csharp/model-data/object-models-define-custom-setters-description.rst

@@ -0,0 +1,2 @@
+In the following code, the private ``email`` property is stored in the database,
+but the public ``Email`` property, which provides validation, is not persisted.

source/includes/sdk-examples/model-data/define-custom-setters.rst

@@ -0,0 +1,71 @@
+.. tabs-drivers::
+
+   tabs:
+     - id: cpp-sdk
+       content: |
+
+         .. literalinclude:: /examples/MissingPlaceholders/example.cpp
+            :language: cpp
+            :copyable: false
+
+     - id: csharp
+       content: |
+
+         .. literalinclude:: /examples/generated/dotnet/Objects.snippet.custom-setter.cs
+            :language: csharp
+
+     - id: dart
+       content: |
+
+         .. literalinclude:: /examples/MissingPlaceholders/example.dart
+            :language: dart
+            :copyable: false
+
+     - id: java
+       content: |
+
+         .. literalinclude:: /examples/MissingPlaceholders/example.java
+            :language: java
+            :copyable: false
+
+     - id: java-kotlin
+       content: |
+
+         .. literalinclude:: /examples/MissingPlaceholders/example-java-kotlin.kt
+            :language: kotlin
+            :copyable: false
+
+     - id: javascript
+       content: |
+
+         .. literalinclude:: /examples/MissingPlaceholders/example.js
+            :language: javascript
+            :copyable: false
+
+     - id: kotlin
+       content: |
+
+         .. literalinclude:: /examples/MissingPlaceholders/example.kt
+            :language: kotlin
+            :copyable: false
+
+     - id: objectivec
+       content: |
+
+         .. literalinclude:: /examples/MissingPlaceholders/example.m
+            :language: objectivec
+            :copyable: false
+
+     - id: swift
+       content: |
+
+         .. literalinclude:: /examples/MissingPlaceholders/example.swift
+            :language: swift
+            :copyable: false
+
+     - id: typescript
+       content: |
+
+         .. literalinclude:: /examples/MissingPlaceholders/example.ts
+            :language: typescript
+            :copyable: false

source/sdk/model-data/object-models.txt

@@ -1076,6 +1076,55 @@ first access, so will never be nil.
 
 .. include:: /includes/sdk-examples/model-data/define-default-value-for-property.rst
 
+.. _sdks-custom-setters:
+
+Define Custom Setters
+~~~~~~~~~~~~~~~~~~~~~
+
+For some platforms and languages, the idiomatic developer experience involves
+defining custom setters. The SDK does not directly persist properties using
+custom setters. Instead, you can store the property value in a private property,
+and then map that value to a public property that uses the custom setter.
+
+The SDK stores the private property, while you modify its value through the
+public property.
+
+.. tabs-drivers::
+
+   .. tab::
+      :tabid: cpp-sdk
+
+   .. tab::
+      :tabid: csharp
+
+      .. include:: /includes/api-details/csharp/model-data/object-models-define-custom-setters-description.rst
+
+   .. tab::
+      :tabid: dart
+
+   .. tab::
+      :tabid: java
+
+   .. tab::
+      :tabid: java-kotlin
+
+   .. tab::
+      :tabid: javascript
+
+   .. tab::
+      :tabid: kotlin
+
+   .. tab::
+      :tabid: objectivec
+
+   .. tab::
+      :tabid: swift
+
+   .. tab::
+      :tabid: typescript
+
+.. include:: /includes/sdk-examples/model-data/define-custom-setters.rst
+
 .. _sdks-model-unstructured-data:
 
 Model Unstructured Data
@@ -1252,7 +1301,16 @@ a projection to make data available in a specific form, but persist it in a
 different form.
 
 For example, you might want to work with persisted data in a different way in
-a view model or based on certain business logic.
+a view model or based on certain business logic. This simplifies using and
+testing SDK objects in your application.
+
+With projection, you can use a subset of your object's properties directly in
+the UI, or transform them. When you use a projection for this, you get all the
+benefits of the SDK's live objects:
+
+- The class-projected object live updates
+- You can observe it for changes
+- You can apply changes directly to the properties in write transactions
 
 Projection is currently only available in the Swift SDK.
 

source/sdk/model-data/property-types.txt

@@ -80,3 +80,18 @@ Define a Set Property
 
 Define a Dictionary Property
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. _sdks-relationship-property-types:
+
+Relationship Property Types
+---------------------------
+
+.. _sdks-other-property-types:
+
+Other Property Types
+--------------------
+
+.. _sdks-enum-property:
+
+Define an Enum Property
+~~~~~~~~~~~~~~~~~~~~~~~