You are creating a SharePoint site that will be accessed remotely. You need to optimize the SharePoint experience for all mobile devices. What should you configure?

Custom list views modify how list data is presented in a specific view but do not address overall page layout or navigation for mobile devices.

Image renditions optimize image cropping and sizing for performance but do not control the overall site layout or navigation experience on mobile devices.

Variations are used to manage multilingual or region-specific content publishing, not to adapt site design for different device form factors.

Design Manager is a tool for importing and converting HTML designs into SharePoint master pages but does not itself configure device-specific rendering rules.

Device channels allow administrators to define rules based on user-agent strings to route mobile devices to specific channels with tailored master pages and CSS. This is the primary SharePoint mechanism for delivering a device-specific rendering experience without requiring separate sites. Each channel can be mapped to a distinct design so phones, tablets, and desktops each receive appropriate layouts.