CharPad
A Windows editor for C64 character sets, tiles and maps, and the default tool for graphics in new C64 games and demos.
C64 backgrounds are nearly always built from characters: 8×8-pixel cells drawn from a set of 256 and laid out on a 40×25 grid. CharPad, from Subchrist Software, the makers of SpritePad, lets an artist draw the characters, assemble them into larger tiles and lay the tiles out on a map, with the VIC-II's colour rules for hires and multicolour enforced throughout.
The real value is in reuse. The program shows how many unique characters a screen needs and hunts down duplicates, because 256 runs out fast. Export produces raw data that drops straight into an assembler. It is modern in its comforts and stubbornly old-fashioned in its limits, which is precisely why people use it.