For the purposes of Virtualmin, a mobile device is one that has a small screen and a limited web browser. Some examples would be a Treo, Sidekick, some cellphones, PDA or the iPhone. Because the browsers on these devices typically do not support Javascript, DHTML or complex CSS, the standard Virtualmin user interface does not work well. For this reason, a separate theme has been developed that optimized the UI for use from such devices.

Unlike most Webmin themes, this one is not typically selected by the user explicitly. Instead it is used either when Virtualmin is accessed via a browser on a mobile device (identified by the user agent), or when the URL starts with a specific suffix like m or mobile.

The mobile device theme for Virtualmin allows you to access all the same features that you could via a regular browser, including all Webmin modules. However, some modules that are not part of Webmin have not been fully converted to a mobile-friendly UI, and so will not be as usable. But core Virtualmin operations like creating domains, managing users and installing scripts are fully supported.

To install the theme package on a Redhat, Fedora or CentOS system, use the command :

yum install wbt-virtual-server-mobile

or on Debian or CentOS, use :

apt-get install webmin-virtual-server-mobile

Alternately, you can install it using the Virtualmin Package Updates module.

Once the theme is installed, you probably want to enable it for mobile browsers. This can be done as follows :

1. Go to the Webmin Configuration module, and click on Mobile Device Options.
2. From the Theme for mobile browsers module, select Virtualmin Mobile Theme.
3. Since the normal Webmin login page is not particularly friendly for mobile devices, you should change Force use of HTTP authentication? to Yes.
4. Finally, click Save.

Once the theme is enabled, just go to the Virtualmin administration URL (like https://yourserver:10000/) using your mobile browser. As long as the browser's user agent is detected correctly, you should see a text-only page with links to list all servers, edit a specific server, manage system settings and so on.

Unlike the regular framed theme, to manage a server you must first either select it from the List virtual servers page, or enter the domain name into the Edit server box. This will bring up a page with links for all the possible actions for that server, such as editing features, users, aliases, scripts and databases.

The same theme that lets you access Virtualmin can also be used with the Usermin webmail interface on port 20000. However, this requires at least version 1.310 of Usermin and the 1.5 version of the mobile theme.

Again, all webmail and Usermin functions are available, except for the HTML editor for composing rich-text email. Also, all popup windows for selecting things like email addresses are disabled, as both the Javascript needed to invoke them and the ability to actually open a new window are unlikely to work.

The installation procedure is the same as the theme for Webmin, but the package is named ubt-virtual-server-mobile on Redhat-based systems, and usermin-virtual-server-mobile on Debian and Ubuntu. To enable it, use the Mobile Device Options page in the Usermin Configuration module, with the same selections.

If that page is missing on your system (because you have an older Webmin release), you can instead run the following commands :

echo mobile_preroot=virtual-server-mobile >>/etc/usermin/miniserv.conf
echo mobile_prefixes=m. >>/etc/usermin/miniserv.conf
echo mobile_theme=virtual-server-mobile >>/etc/usermin/config
/etc/usermin/restart

To use the new mobile theme, just login to Usermin at the regular URL using a mobile device like a Treo or cellphone. Instead of the regular UI, you should see a text-only page with links for your mail folders, a search form and links for folder management, editing your addressbook and other mail-related settings.

When viewing the contents of a folder a slightly different text-only layout is used, which avoids wide tables that don't render well on mobile browsers. Also, the design of the address book page has been changed to make it more mobile-friendly. However, almost all mail reading functionality has been preserved - although some features are not supported, such as uploading attachments and the HTML editor when composing mail.