You can store the install files on the SD card but you will not be able to install them using the BB exclusively. You will still need to connect to a PC and enable mass storage. Then use the PC to access your SD card and run the install process from the PC. Think "jump drive."
Treat your password like your toothbrush. Don't let anybody else use it, and get a new one every six months. Clifford Stoll
The only things that will "run" on the SD care are pictures, music and ringtones. You can store other data there as mentioned above, but you cannot run apps from the card.
If you put a .jad file on your SD card and then go into the file explorer and select the .jad file, it will install the app to your device like it would as an OTA install.
The difference between stupidity and genius is that genius has its limits. When you take things for granted, the things you are granted, get taken. Even a mosquito doesn't get a pat on the back until it starts to work.
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