VTech Variety, from 1983, is a particularly interesting LCD handheld because it was not limited to a single game. It used small interchangeable cartridges containing the LCD screen and the logic required for each title; the main unit provided the case, controls and power. Six games are known for the system. At a time dominated by fixed-game LCD handhelds, Variety applied the concept of interchangeable software to a portable device, an unusual solution before cartridge-based handhelds became established.