These two volumes describe the use of all available functions for development of Java-based applications, along with the specific BlackBerry or Java ME APIs available to developers. These two guides are the first place you should consult in terms of the capabilities for Java development on BlackBerry devices.

Volume 1 describes functions usable by all Java-based BlackBerry applications. Volume 2 describes the functions that require a digital signature in order to be used.

Version 4.1 is the correct version for development of applications on BlackBerry 7100i and 7520 devices that have the 4.1 version of the BlackBerry OS.