NS and APT Services
The NS system module is the first module launched after the core processes sm, fs, pm, loader, and pxi are loaded. This module is launched by the pm process, with the titleID loaded from REG_NSTID. NS first launches ErrDisp, then the menu. If launching home menu fails,(on dev units the titleID seems to be loaded from config) NS will attempt to launch the alternate menu.
This module also has services for launching and possibly managing titles.