WWDC24: What’s new in location authorization | Apple

Summary

In this presentation, Adam Driscoll introduces new features for location authorization in Core Location, focusing on CLServiceSession for expressing authorization needs and Diagnostic Properties for understanding authorization status. He explains how to use these tools to simplify and robustify location-based app development, ensuring apps can adapt to user authorization preferences and system changes.

Takeaways

• 📍 **Introduction to Core Location**: Core Location is essential for apps to access device location for features like Maps or nearby events.
• 🔐 **New APIs for Location Updates**: CLLocationUpdate and CLMonitor were introduced for asynchronous location updates and state-change events.
• 📱 **Permission Requirement**: To use Core Location, apps must request permission from users, which can be complex in Swift.
• 🛠️ **Simplification with CLServiceSession**: CLServiceSession is a new way to simplify location authorization code and make it more robust.
• 🎯 **Authorization Goals**: CLServiceSession allows apps to declare their authorization needs directly to Core Location.
• 🔄 **Session Lifecycle**: Discusses when to create a CLServiceSession and its behavior during app suspension or termination.
• 🔍 **Diagnostic Properties**: A new system of Diagnostic Properties provides contextual understanding of authorization and API object functioning.
• 📈 **Transition from Procedural to Declarative**: Moving to a declarative model for location authorization simplifies the process.
• 🔗 **Linking Sessions to Features**: Sessions should be associated with user-facing features and maintained even when the app goes into the background.
• 🔒 **Handling Authorization Denial**: Diagnostic Properties help understand why an authorization goal cannot be met, like global location service denial.
• 🔄 **Implicit vs. Explicit Sessions**: Implicit sessions through iterating liveUpdates or events, and explicit sessions for more control over authorization requests.

Q & A

What is the main topic of Adam Driscoll's presentation?

Adam Driscoll's presentation is about the new features and improvements in location authorization with Core Location, focusing on CLServiceSession and Diagnostic Properties.

How does Core Location help apps determine the user's location?

Core Location allows apps to determine the user's location by providing APIs that can access latitude and longitude updates, as well as state-change events based on spatial conditions.

What are the two new API objects introduced by Siraj and Nivash last year?

The two new API objects introduced are CLLocationUpdate and CLMonitor, which present an AsyncSequence interface for easy access to location updates and state-change events.

Why is it necessary to get permission from users before using Core Location APIs?

It is necessary to get permission from users to ensure privacy and comply with regulations, as Core Location APIs access sensitive location data.

What is CLServiceSession and how does it simplify the authorization process?

CLServiceSession is a new declarative way to express authorization goals directly to Core Location, simplifying the process by allowing developers to specify what they need for each feature of their app while it is running.

How does the transition from a procedural to a declarative model for location authorization affect app development?

The transition allows developers to focus on what they need (authorization goals) rather than how to achieve it, leading to more robust and easier-to-maintain code.

What is the significance of the 'Nav' key in the context of CLServiceSession?

The 'Nav' key is used to specify the purpose of needing full accuracy for navigation within the app's location authorization purpose localization resources, providing context for users when Core Location requests temporary full accuracy authorization.

Why should CLServiceSession objects be considered immutable and how should they be managed?

CLServiceSession objects should be considered immutable because they represent the authorization goals of the app. They should be layered and not replaced as needs change, ensuring that the app's authorization requests are aligned with its features.

How do implicit service sessions in Core Location APIs like liveUpdates and Monitor.events relate to authorization goals?

Implicit service sessions represent a goal authorization state of .whenInUse while iterating, aligning with user-facing features and allowing Core Location to manage authorization requests based on the app's needs.

What are Diagnostic Properties and how do they enhance the functionality of CLServiceSession?

Diagnostic Properties are a new system that provides contextual understanding of the app's current authorization and the functioning of Core Location API objects, allowing the app to respond appropriately to changes in authorization status.

How can developers ensure that their app's location features continue to function correctly when the app is in the background or terminated?

Developers should ensure that their app's process launch logic is aware of ongoing features and re-takes session objects or resumes iterating liveUpdates or Monitor.events as soon as possible upon relaunch, to maintain Core Location's awareness of the app's authorization needs.