Both consoles will outscale the game so they can output it to your display's native resolution
There is no doubt about the fact that the PlayStation 4 and Xbox One are the most powerful of all gaming consoles and they both have been doing pretty well in the gaming industry. However, there have been instances when some third party games have shown a better performance on Sony's console and it is most likely that this trend is going to continue with Ubisoft's upcoming cyberpunk hackathon, Watch Dogs.
The PS4 is certainly going to have an upper hand as far as the native resolution is concerned but both the platforms are going to run the game on the same 30fps frequency which is the gold standard for open-world games. Neither of the gaming consoles is going to sport 1080p natively according to publisher Ubisoft. For some this might come as a surprise because this is contrary to what the PlayStation.com listing had stated before being removed over this weekend.
The PS is going to run the adventures of Aiden Pearce at 900p and the Xbox One owners will see 792p on their flat-screens. Both consoles are known to outscale the game so they can output it to your display's native resolution and this is only going to generate a slight difference which will only be noticed in case you are playing on both consoles side by side.