If you built your app with Mac Catalyst, you can setup OneSignal's XCFramework SDK.
More details in this guide on our blog.
OneSignal does not currently have a dedicated macOS SDK. However, OneSignal can be used to send notifications to macOS apps. Please refer to Apple's documentation to learn how to obtain a push token.
To register a macOS device, call OneSignal's Add a Device POST /players with a
9 to represent the macOS platform, and pass in the push token for the
Updated almost 2 years ago