When should I use SwiftData instead of SQLite?

SwiftData is recommended for modern Swift-native apps with deep SwiftUI integration, while SQLite or GRDB is better for advanced features like Full-Text Search (FTS5) or performance-critical complex joins.

Which directory should I use for re-downloadable content?

Use the Library/Caches/ directory for data that can be re-fetched or regenerated, as the system may purge these files under storage pressure to free up space.

How do I ensure user data is backed up to iCloud?

Store user-created content in the Documents/ directory. For app-specific data that must persist but remain hidden from the user, use the Application Support directory.

What is the best way to sync structured data across devices?

For iOS 17+, SwiftData with CloudKit is the simplest approach. For more complex custom persistence, CKSyncEngine provides a modern way to manage CloudKit synchronization.

iOS Storage Decision Framework

Name: iOS Storage Decision Framework
Author: CharlesWiltgen

byCharlesWiltgen

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233

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Mobile Development

Guides developers through selecting the optimal iOS storage solutions by evaluating data structure, persistence needs, and cloud synchronization requirements.

This skill acts as a comprehensive architectural consultant for Apple platform developers, providing a structured framework for navigating complex data persistence decisions. It helps determine whether to use structured record storage like SwiftData and SQLite or file-based management via FileManager, while identifying the correct filesystem locations to satisfy Apple's backup and purge policies. By integrating modern patterns for iOS 17+, including CKSyncEngine and iCloud Drive, it ensures your app architecture is performant, scalable, and compliant with platform best practices.

Key Features

01Comprehensive decision trees for structured data vs. file-based storage

02Integration guidance for SwiftData, SQLite, and legacy Core Data patterns

03Detailed directory mapping for Documents, Caches, and Application Support

04233 GitHub stars

05Best practices for backup optimization and storage pressure management

06Cloud synchronization strategy selection for CloudKit and iCloud Drive

Use Cases

01Determining the correct iCloud sync method for multi-device data consistency

02Architecting the data persistence layer for a new iOS or macOS application

03Optimizing disk usage to prevent app rejection due to excessive backup bloat

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add charleswiltgen/axiom axiom-storage

For use in Claude.ai and ChatGPT

Download Skill