# Unity developer API references

> Review the C# API for Unity Ads SDK integration, deprecated Unity APIs, and the API deprecation policy.

Review the C# API for Unity Ads SDK integration, deprecated Unity APIs, and the API deprecation policy.

[Unity Ads API reference - C#](/ads-unity/4.19.0/sdk-integration/api/unity-api.md): Use the Unity Ads SDK API in C# to integrate Unity Ads into your apps.
[Unity deprecated APIs](/ads-unity/4.19.0/sdk-integration/api/unity-deprecated-apis.md): Identify deprecated Unity Ads SDK classes, as well as the replacement and removal versions.
[Unity Ads API deprecation policy](/ads-unity/4.19.0/sdk-integration/api/api-deprecation-policy.md): Review Unity's guidelines on API deprecation. Check timelines, notifications, and exceptions for SDK changes.