gnokii is a multisystem tool suite for mobile phones. It provides a library to communicate with a phone hiding the communication protocol. The library handles SMS, phonebook, calendar, phone calls, and other mobile phone capabilities. It supports Nokia-FBUS mobiles, AT-capable phones (most of the mobiles), as well as Symbian-based phones.
gscmxx allows you to access your Siemens cell phone from your (Linux) desktop. gscmxx supports read and write access to phonebooks and the addressbook (if available) and read access to record lists. Furthermore, gscmxx supports downloading and uploading bitmaps to and from the phone. Bitmaps are displayed directly within the application. gscmxx also supports reading and sending SMS.
GSMLIB is a library to access GSM mobile phones through GSM modems. Features include: modification of phonebooks stored in the mobile phone or on the SIM card, reading and writing of SMS messages stored in the mobile phone, sending and reception of SMS messages. Additionally, some simple command line programs are provided to use these features.
libss7 is a userspace library for providing SS7 protocol services to applications. It has a working MTP2, MTP3, and ISUP for ITU and ANSI style SS7, but was written in a manner that will easily allow support for additional national specific variants in the future. For a working reference implementation, see the various link test programs, as well as the Asterisk Open Source PBX.