Starting with the fourth edition of 4.0, applications could utilize a new set of additional system extensions that provide a unified interface for accessing various expansion capabilities.

The simplest examples of these are Secure Digital cards, CompactFlash cards, and so forth. Another possible area of use is with digital cameras, players and so forth.

In other words, expansion technology covers not only input and output and memory gadgets, but also proposes a convenient way to exchange data with other systems.

Click here to go to developer.com and learn how to leverage this technology to improve your mobile applications.