Push Notification - Tester is a macOS application for testing Apple Push Notification Service (APNs) without requiring a backend server. The app allows developers to select a push certificate from the Mac Keychain, enter a device token, choose between the Development or Production environment, edit the JSON payload, and send a test push notification directly to APNs. It is available as a free download from the Mac App Store. The application includes several supporting tools. A push notification tester builds and validates an APNs payload against the 4 KB size limit. An APNs JWT generator signs an ES256 provider token from a .p8 key. A device token checker verifies a token's hex format and length. An APNs error codes reference explains each error reason with a fix checklist. These tools are available free in a browser, alongside additional developer tools such as an Apple device screen size reference and an app icon generator. The typical workflow begins with obtaining an APNs push certificate from the iOS developer and installing it in the Mac Keychain. The user then opens the app, selects the certificate, pastes the device token, selects the environment, edits the JSON payload, and sends the push. The app is designed to keep data on the device wherever possible. It may display ads through Google AdMob and use basic anonymous analytics, but it does not sell personal data. Push Notification - Tester runs on Mac and requires macOS 14.6 or later. The latest version is 2026.10.03, released on 2026-10-13. Terms of Use and Privacy Policy are available through the developer's website.