Some BASIC language enhancements for Commodore 8-bit machines, such as the 1982 DOS Wedge, worked by patching the CHRGOT routine. Even though BASIC is in ROM, every byte that is fetched from a program is processed by a cascaded pair of functions which are copied to RAM, called CHRGET and CHRGOT. Patching CHRGOT so that it jumps to a routine elsewhere in ROM will allow arbitrary functionality will be added to the BASIC interpreter. Although Commodore BASIC V2 has better hooks available, the CHRGET/CHRGOT hook is common to nearly all Microsoft-derived versions of BASIC for the 6502, including AppleSoft.
Did any AppleSoft BASIC enhancements for the Apple install a CHRGOT hook, or did they all use either the Ampersand Hook (which is unique to Applesoft) or the Language Card (copying AppleSoft to RAM and running it from there)?