A seven-seater compact MPV version, the Grand C4 Picasso, was introduced in 2006, while a five-seater called the C4 Picasso was introduced in 2007.
Citroën C4 BioFlex is a bioethanol flexible fuel vehicle.
Citroën C4 Hybride HDi is a hybrid diesel-electric car. PSA Peugeot Citroën could market its Hybride HDi vehicles in 2010 .
Included in the hybrid vehicle strategy HYmotion .
The motoring press has described it as a return to the more bold and unconventional design approach for which Citroën was famed before the 1990s, when Citroën designs became much more conservative (ZX, Saxo). The distinctive exterior styling of the C4 is the work of Donato Coco. The current C4 is not the first Citroën to bear this designation; Citroën previously produced a C4 in 1928. The quirky rear-end styling of the three-door C4 brought back many memories of the 1995 Mazda 323 F three-door.
A major selling-point of the C4 is its extensive use of technology. For example, the car features the "Lane Departure Warning System" (only in the top-of-the-range "Exclusive" model), which alerts the driver if he or she crosses a road marking without using the turn signals; directional headlights; perfume dispenser integrated into the ventilation system; translucent dashboard, transparent glass roof; ESP (Electronic Stability Program), and a fixed steering wheel hub which lets the driver operate several functions of the car without removing his or her hands from the wheel. The fixed hub also allows for the first production use of a "shaped" driver airbag. Because the hub maintains a constant position, the airbag can be optimally shaped to spread the load across the greatest possible area of the driver's body in a collision, thus reducing the chances of serious injury. In addition, the car features an innovative centrally mounted translucent LCD speedometer display that remains clearly visible in all lighting conditions.