Test your existing apps against EventKit API latest changes. View Technote TN3153 >

Follow these guidelines to update your app to use the new Calendar access levels. View Technote TN3152 >

Learn which networking API is best for you. View Technote TN3151 >

Learn how to fetch and process the most recent changes to the Contacts database. View Technote TN3149 >

Distribute a Metal renderer in a Swift package. View Technote TN3133 >

Use AVAudioConverter to perform sample rate conversions between PCM audio buffers. View Technote TN3136 >

Migrate your notarization workflows to notarytool from the deprecated altool. View Technote TN3147 >

Ensure that your app’s local receipt validation is compatible with intermediate certificates that require using the SHA-256 algorithm. View Technote TN3138 >

Learn about the usage and requirements of “Ambient Viewing Environment” metadata with Dolby Vision™ Profile 8.4 playback. View Technote TN3145 >

Understand dataless files and how to minimize the performance impact as the system materializes them. View Technote TN3150 >

Learn about the supported use cases for low-level networking on watchOS. View Technote TN3135 >

Learn how the keychain on macOS differs from other Apple platforms. View Technote TN3137 >

About technotes Technotes are focused, timely documents from Apple Developer Technical Support. They explore a wide range of development topics and provide guidance for developers creating apps and accessories for all of Apple’s platforms. Learn about specific development topics through these in-depth technical articles. You can subscribe to the RSS feed to get notified when new technotes are published.  Each technote has its own Developer Forums post. We encourage you to discuss the technotes and share your feedback. Let us know if a technote is helpful, or what we can do to improve it. We would appreciate it if you include a Feedback Assistant (FB) number so we can easily track your feedback, and let you know when it’s resolved. Provide feedback You can provide feedback about a specific technote (or technotes as a whole) using Feedback Assistant. When filing, use the following path when creating new feedback: What are you seeing an issue with? Developer Tools Which area are you seeing an issue with? Developer Documentation What does the documentation issue you are reporting involve? Technotes Please provide the URL of the content you reporting an issue with: The complete URL of the technote, e.g. https://developer.apple.com/documentation/technotes/tn3102-http3-in-your-app (If you wish to leave feedback on Technotes in general, use https://developer.apple.com/documentation/technotes for the URL.) Then complete the remaining fields appropriately. We appreciate and look forward to your feedback.

Learn how provisioning profiles enable third-party code to run on Apple platforms. View Technote TN3125 >

Use an anonymous XPC listener to simplify your XPC testing and debugging. View Technote TN3113 >

Get started with iOS 15’s new HTTP/3 support. View Technote TN3102 >

Explore the various Wi-Fi APIs available on iOS and their expected use cases. View Technote TN3111 >

Review common causes for failing Xcode Cloud builds that originate from helper tools running in a misconfigured build environment. View Technote TN3129 >

Update your app’s architecture build settings to support building macOS, iOS, watchOS and tvOS apps on Apple silicon. View Technote TN3117 >

Learn strategies and techniques for refactoring a single storyboard into multiple storyboards. View Technote TN3123 >