Submitted by drjunior on Tue, 06/04/2013 - 16:32
Here is the very useful command to install a common app as system app. It's not necessary to say that's mandatory that the device needs to be rooted!
Explanation:
#remount system partition with read and write capabilities
#move the app from the sdcard to the /system/app directory
#remount again as read only
#reboot the device