How to delete, disable and exit Demo Live Unit Retail Mode on the Samsung Galaxy S5
1. The first thing to do is to disable the retail mode of the firmware.
2. Go to the app drawer and open an app called Samsung Retail.
3. Go to Configuration Settings and enter the password 5444 to unlock it.
4. Then uncheck “Disable the factory reset” and enter the following password M729Q16K8546.
5. Turn your Samsung Galaxy S5 off and boot into Recovery.
6. Go to Wipe data & factory reset and press OK.
7. The phone will reset and all the applications will get removed.