How to change the demo OS in Sony xperia tablet z I have bought a sony xperia tablet z yesterday.. the showroom dint have the stock right now, so he sold me the demo piece in the display.. it is working fine, so i took it.. but after using it i understand that..it is running some kind of demo settings.. a demo video is being palyed for every 20 minutes.. if i re arrange any icons and go to another screen.. when i came back.. the icons are automatically restored to defaults..similar with volume settings.. how to remove those demo settings.. make it work like usual tablet.. thank you
Since you don't have a dialer app in the tablet, Ali Kabiri's answer can't be directly used. But there's a way to get into a mode where you can enter these "service codes". See this blog post for images.


Open the Contacts app
Exit the initial setup if it pops up
Go to Menu -> Settings
Long-press the blank space in the bottom of the screen, in the middle (see images in link)
A button called "Enter service code" should appear
Tap the button to get a "dialer"
Enter the code *#*#73556673#*#*
Demo mode should now be deactivated!