In 1980, Leica introduced their first compact single-lens reflex camera. Along with interchangeable focusing screens, the camera offered numerous automatic exposure modes: aperture priority with selective or integrated (centre-weighted) metering, as well as shutter priority and program automatic with integrated (centre-weighted) metering. In addition, the camera also offered selective ('spot') metering in manual mode.
In auto-mode, the newly developed shutter offered speeds from 8 to 1/1000 sec, while a mechanical shutter speed of 1/100 sec was available in case of battery failure.
The R4 also differed from its predecessor in terms of its exterior, with the R3's edges and angles having been replaced by a smoother, more modern design.