Nemiver is described as 'standalone graphical C and C++ debugger that integrates in the GNOME desktop environment. It currently features a backend which uses the well known GNU Debugger (gdb)' and is an app in the Development category. There are four alternatives to Nemiver for Linux, BSD and Cygwin. The best alternative is GNU Data Display Debugger, which is both free and Open Source. Other great apps like Nemiver are GDBFrontend (Free), gdbgui (Free, Open Source) and Kdbg (Free, Open Source).
DDD is a graphical front-end for command-line debuggers such as GDB, DBX, WDB, Ladebug, JDB, XDB, the Perl debugger, the bash debugger bashdb, the GNU Make debugger remake, or the Python debugger pydb.