You can set which theme will be use visible for administrator role while logged, or for editor., or any other role created.
Also, you can set which theme will be visible for rest of visitors, that´s rest of people that are not wp users, just visitors..
It´s very easy, just install it, go to Development Themes Options page, choose your roles themes and save..
Put your site under maintenance using some other theme for your site, but let the administrator or any other role be able to see and work theme, let´s say update...
You can test some new theme while rest of visitors still see the current one...
In fact, you can show theme for any role that is actived, default ones, or any other role created by some other plugin.
You can also turn Off the plugin, order to use the theme for all users and visitors...
Version 0.2 for Options plugin page under Appearance -> Development Themes Options..
Browse the code, check out SVN repository, or subscribe to the development log by RSS...
Included thumbnail preview of themes on theme list..
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