Ryan Duff

Allow admin users to switch which theme they use on your WordPress, WordPress MU, or BuddyPress site. Adds a drop down on the Admin Bar with a drop down to choose from installed themes.

Admin Bar Theme Switcher

Allow admin users to switch which theme they use on your WordPress, WordPress MU, or BuddyPress site.  Adds a drop down on the Admin Bar with a drop d …

John P. Bloch

Create child themes from any non-child theme with the click of a button.
This plugin is multisite compatible; if used on a multisite network, controls for creating child themes will be in the network admin instead of the regular site admin. Pick the parent theme from the dropdown and name name your new child theme. You can also change the author name and select files you want to copy from the parent to the new theme.
Click the button and you’re all set!

Child Themify

Create child themes with the click of a button.

Admin Bar Theme Switcher vs Child Themify