The GTS badge has expanded to 5 variants in Porsches 911 line up. The Carrera GTS with rear-wheel drive, Carrera 4 GTS with all-wheel drive both in coupe and convertible versions and the 911 Targa GTS in all-wheel drive.
You will be hard pressed to notice the visual differences of the GTS models, but they are there if you look hard. Every GTS vehicle uses the wider all-wheel drive body of the 911 family, and the front bumper spoiler sits lower with the rear spoiler extending higher. Porsche is known for only giving minor changes to the visual design of the 911, and they have continued that trend here.