My answer is just for 2012 TV (E/ES/EH) Series:
- Unzip your exported application to USB Drive with folder named your apps
- Example: SampleApps_1.000_Asia_20140218.zip so resulting X:\SampleApps\config.xml
- Plug-on the USB Drive
- Turn off the TV
- Turn on the TV and go to smart hub
The USB Drive "must" plugged-on when using the Apps because the apps is not installed on TV, just read from USB