Mobile and Offline Developer Guide

Mobile App Development with Lightning Web Components and LWC Offline
Create Mobile-Ready Components
Use Mobile Device Features in Mobile Apps
Offline Considerations and Limitations
Offline Environment Details
Use Salesforce Features While Offline
Use GraphQL While Mobile and Offline
Use Apex While Mobile and Offline
Use Apex in Lightning Web Components While Online
Reactive Apex Wires
Imperative Apex
Enable Caching of Apex Results
Apex Results Are Separate from Other Primed Data
Understand Apex Behavior While Offline
Additional Considerations for Apex in an Offline-Enabled Mobile App
Additional Documentation for Apex in Lightning Web Components
Use Images in an LWC Offline-Enabled Component
Upload Images While Offline
Use Third-Party JavaScript in an LWC Offline-Enabled Component
Navigation
Development Tools and Processes
Quick Start Tutorials
PDF

Use Apex in Lightning Web Components While Online

The essentials of using Apex within Lightning web components are described in "Call Apex Methods" in the Lightning Web Components Developer Guide. While Apex features behave as documented when a client device is online, there are additional features available within an offline-enabled mobile app.

To take advantage of these features, you need to know the basics of using Apex within Lightning web components. In particular, there are two different ways of calling an Apex method from a Lightning web component.