The Mobile Switch (Varnish) module provides a simple automatic theme switch functionality for mobile devices, utilising Varnish for detecting the user-agent and providing proper cacheable pages using the same URLs per mobile device group.

Difference between this module and Mobile Switch

Initially we were using Mobile Switch but for our busy site we couldn't afford for the user-agent detection to be taking place within Drupal. Anywhere we can avoid bootstrapping Drupal the better to relieve the load on our servers. Note this module is NOT a fork of Mobile Switch, see the section on "How it works" for more details.

How it works

The module works by adding a device key to the beginning of the Varnish hash. This ensures that each device group maintains its own separate page cache meaning, entire separately themed pages can be used for each group. NOTE: you will not need this as a solution should you be using a responsive theme as you will then only be using one page cache across all your devices.

Similar modules

Credits

Loosely based around the work on this page - which in turn, appears to be based on this page!

Written as a proof of concept for The British Council but not used... It's a long story...

Mobile Switch (Varnish version)

Issues