ios-data

Identify iOS data persistence strategies across SwiftData, Core Data, UserDefaults, Keychain, and CloudKit.

6|Updated Mar 16, 2026
One-click install
npx skills add https://github.com/koshkinvv/ios-agent-skills --skill ios-data-koshkinvv
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: ios-data
Source: https://github.com/koshkinvv/ios-agent-skills/tree/main/skills/ios-data
Command: npx skills add https://github.com/koshkinvv/ios-agent-skills --skill ios-data-koshkinvv

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

iOS data persistence across multiple storage options (SwiftData, Core Data, UserDefaults/@AppStorage, Keychain, iCloud) to help developers design reliable, scalable data layers.

Core Features & Use Cases

  • Guidance on selecting the right storage backend based on data sensitivity, size, and query needs.
  • In-depth references and patterns for SwiftData, Core Data, @AppStorage, and Keychain.
  • Migration, cloud syncing, offline support, and cross-device data access.

Quick Start

Install the ios-data skill and then request guidance to implement a secure, scalable, and migratable data persistence layer across the app.

Frequently Asked Questions about ios-data

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I choose the right iOS data persistence strategy between SwiftData and Core Data?

Choosing an iOS data persistence strategy involves evaluating data sensitivity, size, and query needs. SwiftData offers modern container setup and model definitions, while Core Data provides mature patterns for complex migrations and performance tuning.

How do I handle Core Data migrations and offline support in an iOS app?

Handling Core Data migrations and offline support requires designing a scalable data layer with proper container setup. This Skill provides in-depth patterns for managing model definitions, error handling, and ensuring data availability without a network connection.

Does SwiftData work with CloudKit for cross-device cloud sync?

Yes, SwiftData works with CloudKit for cross-device cloud sync. This Skill covers how to implement cloud syncing and offline support, ensuring reliable data access across iOS devices through proper container configuration and error handling.

What is the best way to store sensitive user data securely in iOS using Keychain?

Storing sensitive user data securely in iOS requires using Keychain for encrypted storage. This Skill provides guidance on selecting the right storage backend based on data sensitivity, ensuring secure storage practices are applied to your app.

When should I use UserDefaults or @AppStorage instead of SwiftData?

Use UserDefaults or @AppStorage instead of SwiftData for small, non-sensitive data preferences. This Skill helps identify the right storage backend by evaluating data size and query needs, ensuring reliable and scalable data layer design.

Why does my SwiftData model definition cause performance issues during cloud sync?

SwiftData performance issues during cloud sync often stem from improper container setup or model definitions. This Skill covers performance tuning and error handling patterns to optimize data persistence layers and resolve syncing bottlenecks.