A new ASUS ZenFone 4 Pro leak suggests that the phone will come with a 21-megapixel dual rear camera module, along with a handful of other specifications. The front-facing camera details are absent here but it is stated that the rear cameras come with 2x zoom. While the entire specs list is not mentioned in the leak, alongside the rear camera setup the phone is rumored to come powered by Qualcomm's Snapdragon 835 processor and Adreno 540 graphics processor. Also listed is Android 7.1.1 Nougat for the software version and 6GB of RAM, as well as 64GB of internal storage space. While expandable storage support is not mentioned, ASUS is known for adding expandable storage support in its previous ZenFone lineups so users should expect to see it with the ZenFone 4 Pro as well.
In addition to the leaked specifications mentioned above, there were also a few images that leaked showing off parts of the phone. In one of these images you can see the dual rear camera setup and while the megapixels aren't shown, it does show that the phone has 2x zoom, adding credit to the leaked information, though this is likely where those details came from. That being said, this is more than likely to be a digital zoom and not an optical zoom as the camera module is enclosed with no visible way for the cameras to zoom out physically.
The other included images show the Android Nougat icon in the status bar, while one of the images is of the About Phone screen which details Android 7.1.1 as the software version, as well as the model number of the phone which is ASUS Z01GS. In addition to the ZenFone 4 Pro, there is at least two other devices in the ZenFone 4 lineup that are expected. The ZenFone 4 Max, which was recently leaked earlier on in May, rumored to come with a Snapdragon 630 or Snapdragon 660 chipset, as well as the ZenFone 4 standard model, which has been teased by ASUS as of a little earlier this month. There is still no release date for the ZenFone 4 Pro or any of the other phones in the series yet, but ASUS also hasn't officially announced the ZenFone 4 lineup, so it's possible that a launch will come after it unveils the phones, which is likely to happen at IFA in September.