Two functions tell a template what device the visitor uses:
jrCore_is_mobile_device() is true on phonesjrCore_is_tablet_device() is true on tabletsUse them in an {if} tag:
{if jrCore_is_mobile_device()}
{* content for phones *}
{elseif jrCore_is_tablet_device()}
{* content for tablets *}
{else}
{* content for desktops *}
{/if}Elastic 2 uses them in header.tpl and footer.tpl to switch to a phone menu.
To change only the look, CSS is usually simpler. Elastic 2 has override_mobile.css and override_tablet.css for this. Change them on the Style tab, or in a clone's files.